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gistfile1.txt

排列的问题，求一个集合元素的全排列。

整数集合s和一个整数sum，求集合s的所有子集su,使得su的元素之和为sum


  1 #include <iostream>
  2
  3 using namespace std;
  4
  5
  6 int sum = 10;
  7 int subsum = 0;
  8 int s[5]= {1, 3, 6, 4, 2};
  9 int x[5]={0};
 10 int N = 5;
 11
 12 void print(){
 13     for (int index = 0; index < N; ++index)
 14         if (x[index] == 1)
 15             cout << s[index] << " ";
 16     cout << endl;
 17 }
 18
 19 void sumSet(int index){
 20     if (index >= N){
 21         if (sum == subsum)
 22             print();
 23         return;
 24     }
 25     if (subsum < sum){
 26         x[index] = 1;
 27         subsum += s[index];
 28         sumSet(index + 1);
 29         subsum -= s[index];
 30     }
 31     x[index] = 0;
 32     sumSet(index + 1);
 33 }
 34
 35 int main(){
 36     sumSet(0);
 37
 38     return 0;
 39 }