/in/foo.cc: In function 'int main()':
/in/foo.cc:13:9: warning: unused variable 'm' [-Wunused-variable]
  int n, m,flag;
         ^
/in/foo.cc:13:11: warning: unused variable 'flag' [-Wunused-variable]
  int n, m,flag;
           ^
/in/foo.cc:14:12: warning: unused variable 'c' [-Wunused-variable]
  long long c,low,sum=0;
            ^
/in/foo.cc:14:14: warning: unused variable 'low' [-Wunused-variable]
  long long c,low,sum=0;
              ^
/in/foo.cc:15:12: warning: unused variable 'max' [-Wunused-variable]
  int i, j, max=0,k,num=0;
            ^