/in/foo.cc: In function 'int main()':
/in/foo.cc:41:12: warning: unused variable 'i' [-Wunused-variable]
    int A,B,i;
            ^
/in/foo.cc: In function 'int isCount(int, int)':
/in/foo.cc:26:11: warning: 'num' may be used uninitialized in this function [-Wmaybe-uninitialized]
    return num;
           ^~~
/in/foo.cc: In function 'int main()':
/in/foo.cc:43:22: warning: 'num' may be used uninitialized in this function [-Wmaybe-uninitialized]
    cout<<isCount(A,B);
                      ^