Run id: 141020

Main.cc: In function 'int main()':
Main.cc:9:17: error: 'j' was not declared in this scope
       for(int k=j;j<=n-k+1;j++){
                 ^
Main.cc:5:10: warning: unused variable 'sum' [-Wunused-variable]
    int n,sum=1;
          ^