poj 2466 Pairsumonious Numbers

poj 2466 Pairsumonious Numbers

#include<iostream>#include<cstdio>#include<cstring>#include<cmath>#include<algorithm>using namespace std;int a[50];int x[15];int flag[50];bool cmp(int x, int y){    return x < y;}int main(){    int n;    while(scanf("%d", &n) != EOF){        int m = n * (n - 1) / 2;        for(int i = 1; i <= m; i++) scanf("%d", &a[i]);        sort(a + 1, a + 1 + m, cmp);        bool corr;        for(int i = 3; i <= m; i++){ memset(flag, 0, sizeof(flag)); x[1] = (a[1] + a[2] - a[i]) / 2; x[2] = (a[i] + a[1] - a[2]) / 2; x[3] = (a[2] + a[i] - a[1]) / 2; if((a[1] + a[2] - a[i]) % 2 != 0 || (a[i] + a[1] - a[2]) % 2 != 0 || (a[2] + a[i] - a[1]) % 2 != 0){     corr = false;     continue; } flag[1] = flag[2] = flag[i] = 1; int k = 0; while(4 + k <= n){     for(int j = 1; j <= m; j++){         if(flag[j] == 0){  flag[j] = 1;  x[4 + k] = a[j] - x[1];  break;         }     }     for(int j = 1; j < 4 + k; j++){         for(int l = 1; l <= m; l++){  if((a[l] == x[4 + k] + x[j]) && flag[l]==0){      flag[l] = 1;      break;  }         }     }     k++; } corr = true; for(int j = 1; j <= m; j++){     if(flag[j] == 0){         corr = false;         break;     } } if(corr == true)     break;        }        if(corr == false) printf("Impossiblen");        else{ for(int i = 1; i <= n; i++)     printf("%d ",x[i]); printf("n");        }    }    return 0;}