View difference between Paste ID: 4PqMawrP and wd68j1jB

 #include <iostream>
 #include <vector>
 
 using namespace std;
 int main()
 {
-    int n, sum = 0;
+    int n, sum;
     cin >> n;
     vector<int> a(n);
     vector<int> b(n);
     vector<int> c(n);
     for (int i = 0; i < n; i ++)
     {
         cin >> a[i];
         sum += a[i];
         b[i] = 0;
         c[i] = 1;
     }
     cout<<sum<<endl;
     b[n-1] += 1;
     int sum1=0, flag = 0, flag1 = 0;
     vector<int> null(b);
     for (int i = 1; i < sum; i++)
     {
         do
         {
             for(int k = 0; k < b.size(); k++)
                 sum1 += b[k]*a[k];
             if(sum1 == i)
                 flag++;
             sum1 = 0;
             b[n-1]+=1;
             for (int k = b.size()-1; k>=0; k--)
                 if (b[k]>1)
                 {
                     b[k] = 0;
                     b[k-1] += 1;
                 }
         } while (b != c);
         if (flag == 0)
         {
             cout<<i;
             flag1++;
             break;
         }
         else
         {
             flag = 0;
             b = null;
         }
     }
     if (flag1 == 0)
         cout<<++sum;
 }