foo.cc: In function 'int main()':
foo.cc:27:20: warning: format '%d' expects argument of type 'int', but argument 2 has type 'long long int' [-Wformat=]
  printf("%I64d",ans);
                    ^
foo.cc:9:10: warning: unused variable 'k' [-Wunused-variable]
  int i,j,k;
          ^
foo.cc:11:7: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
  scanf("%d%d",&n,&m);
  ~~~~~^~~~~~~~~~~~~~
foo.cc:15:28: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
      for(j=1;j<=m;j++)scanf("%d",&s[i][j]);
                       ~~~~~^~~~~~~~~~~~~~~