/in/foo.cc: In function 'int count_7(int)':
/in/foo.cc:12:9: warning: unused variable 'm' [-Wunused-variable]
     int m = 1;
         ^
/in/foo.cc: In function 'int main()':
/in/foo.cc:36:11: warning: statement has no effect [-Wunused-value]
     for (l; l<=r; l++)
           ^