| 1 | // | 
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| 2 | // Cforall Version 1.0.0 Copyright (C) 2017 University of Waterloo | 
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| 3 | // | 
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| 4 | // The contents of this file are covered under the licence agreement in the | 
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| 5 | // file "LICENCE" distributed with Cforall. | 
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| 6 | // | 
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| 7 | // quickSort.c -- In-place concurrent quick-sort: threads are created to partition to a specific depth, then sequential | 
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| 8 | //              recursive-calls are use to sort each partition. | 
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| 9 | // | 
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| 10 | // Author           : Peter A. Buhr | 
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| 11 | // Created On       : Wed Dec  6 12:15:52 2017 | 
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| 12 | // Last Modified By : Peter A. Buhr | 
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| 13 | // Last Modified On : Fri Jun 21 08:28:20 2019 | 
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| 14 | // Update Count     : 149 | 
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| 15 | // | 
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| 16 |  | 
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| 17 | #include <fstream.hfa> | 
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| 18 | #include <stdlib.hfa> | 
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| 19 | #include <kernel.hfa> | 
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| 20 | #include <thread.hfa> | 
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| 21 | #include <string.h>                                                                             // strcmp | 
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| 22 |  | 
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| 23 | forall( otype T | { int ?<?( T, T ); } ) { | 
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| 24 | thread Quicksort { | 
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| 25 | T * values;                                                                             // communication variables | 
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| 26 | int low, high, depth; | 
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| 27 | }; | 
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| 28 |  | 
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| 29 | void ?{}( Quicksort(T) & qs, T values[], int size, int depth ) { | 
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| 30 | qs.values = values;  qs.low = 0;  qs.high = size;  qs.depth = depth; | 
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| 31 | } // Quicksort | 
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| 32 |  | 
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| 33 | void main( Quicksort(T) & qs ) {                                        // thread starts here | 
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| 34 | // nested routines: information hiding | 
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| 35 |  | 
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| 36 | void ?{}( Quicksort(T) & qs, T values[], int low, int high, int depth ) { | 
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| 37 | qs.values = values;  qs.low = low;  qs.high = high;  qs.depth = depth; | 
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| 38 | } // Quicksort | 
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| 39 |  | 
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| 40 | void sort( T values[], int low, int high, int depth ) { | 
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| 41 | int left, right;                                                        // index to left/right-hand side of the values | 
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| 42 | T pivot;                                                                        // pivot value of values | 
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| 43 | T swap;                                                                         // temporary | 
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| 44 |  | 
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| 45 | //verify();                                                                     // check for stack overflow due to recursion | 
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| 46 |  | 
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| 47 | // partition while 2 or more elements in the array | 
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| 48 | if ( low < high ) { | 
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| 49 | pivot = values[low + ( high - low ) / 2]; | 
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| 50 | left  = low; | 
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| 51 | right = high; | 
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| 52 |  | 
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| 53 | // partition: move values less < pivot before the pivot and values > pivot after the pivot | 
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| 54 | do { | 
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| 55 | while ( values[left] < pivot ) left += 1; // changed values[left] < pivot | 
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| 56 | while ( pivot < values[right] ) right -= 1; | 
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| 57 | if ( left <= right ) { | 
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| 58 | swap = values[left];                    // interchange values | 
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| 59 | values[left]  = values[right]; | 
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| 60 | values[right] = swap; | 
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| 61 | left += 1; | 
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| 62 | right -= 1; | 
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| 63 | } // if | 
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| 64 | } while ( left <= right ); | 
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| 65 |  | 
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| 66 | // restrict number of tasks to slightly greater than number of processors | 
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| 67 | if ( depth > 0 ) { | 
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| 68 | depth -= 1; | 
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| 69 | Quicksort(T) rqs = { values, low, right, depth }; // concurrently sort upper half | 
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| 70 | //Quicksort lqs( values, left, high, depth ); // concurrently sort lower half | 
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| 71 | sort( values, left, high, depth );      // concurrently sort lower half | 
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| 72 | } else { | 
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| 73 | sort( values, low, right, 0 );          // sequentially sort lower half | 
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| 74 | sort( values, left, high, 0 );          // sequentially sort upper half | 
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| 75 | } // if | 
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| 76 | } // if | 
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| 77 | } // sort | 
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| 78 |  | 
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| 79 | with( qs ) { | 
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| 80 | sort( values, low, high, depth ); | 
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| 81 | } // with | 
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| 82 | } // main | 
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| 83 | } | 
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| 84 |  | 
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| 85 | bool convert( int & val, const char * nptr ) {                  // convert C string to integer | 
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| 86 | char * eptr; | 
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| 87 | int temp = strto( nptr, &eptr, 10 );                            // do not change val on false | 
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| 88 | // true => entire string valid with no extra characters | 
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| 89 | return *nptr != '\0' && *eptr == '\0' ? val = temp, true : false; | 
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| 90 | } // convert | 
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| 91 |  | 
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| 92 | void usage( char * argv[] ) { | 
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| 93 | sout | "Usage:" | argv[0] | "( -s unsorted-file [ sorted-file ] | -t size (>= 0) [ depth (>= 0) ] )"; | 
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| 94 | exit( EXIT_FAILURE );                                                           // TERMINATE! | 
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| 95 | } // usage | 
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| 96 |  | 
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| 97 |  | 
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| 98 | #define ELEMTYPE int | 
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| 99 |  | 
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| 100 | int main( int argc, char * argv[] ) { | 
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| 101 | ifstream & unsortedfile = sin; | 
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| 102 | ofstream & sortedfile = sout;                                           // default value | 
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| 103 | int depth = 0, size; | 
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| 104 |  | 
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| 105 | if ( argc != 1 ) {                                                                      // do not use defaults | 
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| 106 | if ( argc < 2 || argc > 4 ) usage( argv );              // wrong number of options | 
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| 107 | if ( strcmp( argv[1], "-t" ) == 0 ) {                   // timing ? | 
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| 108 | &unsortedfile = (ifstream *)0;                          // no input | 
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| 109 | choose ( argc ) { | 
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| 110 | case 4: | 
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| 111 | if ( ! convert( depth, argv[3] ) || depth < 0 ) usage( argv ); | 
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| 112 | fallthrough; | 
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| 113 | case 3: | 
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| 114 | if ( ! convert( size, argv[2] ) || size < 0 ) usage( argv ); | 
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| 115 | } // choose | 
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| 116 | } else {                                                                                // sort file | 
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| 117 | choose ( argc ) { | 
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| 118 | case 3: | 
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| 119 | &sortedfile = new( (const char *)argv[2] ); // open the output file | 
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| 120 | if ( fail( sortedfile ) ) { | 
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| 121 | serr | "Error! Could not open sorted output file \"" | argv[2] | "\""; | 
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| 122 | usage( argv ); | 
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| 123 | } // if | 
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| 124 | fallthrough; | 
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| 125 | case 2: | 
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| 126 | &unsortedfile = new( (const char *)argv[1] ); // open the input file | 
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| 127 | if ( fail( unsortedfile ) ) { | 
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| 128 | serr | "Error! Could not open unsorted input file \"" | argv[1] | "\""; | 
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| 129 | usage( argv ); | 
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| 130 | } // if | 
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| 131 | } // choose | 
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| 132 | } // if | 
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| 133 | } // if | 
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| 134 | sortedfile | nlOff;                                                                     // turn off auto newline | 
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| 135 |  | 
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| 136 | enum { ValuesPerLine = 22 };                                            // number of values printed per line | 
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| 137 |  | 
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| 138 | if ( &unsortedfile ) {                                                          // generate output ? | 
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| 139 | for () { | 
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| 140 | unsortedfile | size;                                            // read number of elements in the list | 
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| 141 | if ( eof( unsortedfile ) ) break; | 
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| 142 | ELEMTYPE * values = alloc( size );                      // values to be sorted, too large to put on stack | 
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| 143 | for ( counter; size ) {                                         // read unsorted numbers | 
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| 144 | unsortedfile | values[counter]; | 
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| 145 | if ( counter != 0 && counter % ValuesPerLine == 0 ) sortedfile | nl | "  "; | 
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| 146 | sortedfile | values[counter]; | 
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| 147 | if ( counter < size - 1 && (counter + 1) % ValuesPerLine != 0 ) sortedfile | ' '; | 
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| 148 | } // for | 
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| 149 | sortedfile | nl; | 
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| 150 | if ( size > 0 ) {                                                       // values to sort ? | 
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| 151 | Quicksort(ELEMTYPE) QS = { values, size - 1, 0 }; // sort values | 
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| 152 | } // wait until sort tasks terminate | 
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| 153 | for ( counter; size ) {                                         // print sorted list | 
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| 154 | if ( counter != 0 && counter % ValuesPerLine == 0 ) sortedfile | nl | "  "; | 
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| 155 | sortedfile | values[counter]; | 
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| 156 | if ( counter < size - 1 && (counter + 1) % ValuesPerLine != 0 ) sortedfile | ' '; | 
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| 157 | } // for | 
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| 158 | sortedfile | nl | nl; | 
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| 159 |  | 
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| 160 | delete( values ); | 
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| 161 | } // for | 
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| 162 | if ( &unsortedfile != &sin ) delete( &unsortedfile ); // close input/output files | 
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| 163 | if ( &sortedfile != &sout ) delete( &sortedfile ); | 
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| 164 | } else { | 
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| 165 | processor processors[ (1 << depth) - 1 ] __attribute__(( unused )); // create 2^depth-1 kernel threads | 
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| 166 |  | 
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| 167 | ELEMTYPE * values = alloc( size );                              // values to be sorted, too large to put on stack | 
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| 168 | for ( counter; size ) {                                                 // generate unsorted numbers | 
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| 169 | values[counter] = size - counter;                       // descending values | 
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| 170 | } // for | 
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| 171 | { | 
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| 172 | Quicksort(ELEMTYPE) QS = { values, size - 1, depth }; // sort values | 
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| 173 | } // wait until sort tasks terminate | 
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| 174 |  | 
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| 175 | // for ( counter; size - 1 ) {                                  // check sorting | 
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| 176 | //      if ( values[counter] > values[counter + 1] ) abort(); | 
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| 177 | // } // for | 
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| 178 |  | 
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| 179 | delete( values ); | 
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| 180 | } // if | 
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| 181 | } // main | 
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| 182 |  | 
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| 183 | // Local Variables: // | 
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| 184 | // tab-width: 4 // | 
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| 185 | // compile-command: "cfa quickSort.generic.cfa" // | 
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| 186 | // End: // | 
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