/in/foo.cc: In function 'int main()':
/in/foo.cc:52:24: warning: array subscript has type 'char' [-Wchar-subscripts]
         scanf("%d",&a[i][j]);
                        ^
/in/foo.cc:52:27: warning: array subscript has type 'char' [-Wchar-subscripts]
         scanf("%d",&a[i][j]);
                           ^