/in/foo.cc: In function 'int main()':
/in/foo.cc:12:25: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
         for(int i = 0;i <= a.size() - b.size() ;i++){
                         ^
/in/foo.cc:14:25: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
             for(j = 0;j < b.size();j++){
                         ^
/in/foo.cc:19:18: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
             if(j == b.size()){
                  ^