foo.cc: In function ‘int main()’:
foo.cc:16:19: warning: comparison of integer expressions of different signedness: ‘int’ and ‘uint’ {aka ‘unsigned int’} [-Wsign-compare]
   16 |     for (int i=0;i<n;i++) cin>>a[i];
      |                  ~^~
foo.cc:17:19: warning: comparison of integer expressions of different signedness: ‘int’ and ‘uint’ {aka ‘unsigned int’} [-Wsign-compare]
   17 |     for (int j=0;j<m;j++) cin>>b[j];
      |                  ~^~
foo.cc:19:18: warning: comparison of integer expressions of different signedness: ‘int’ and ‘uint’ {aka ‘unsigned int’} [-Wsign-compare]
   19 |     for(int i=0;i<n;i++)
      |                 ~^~
foo.cc:20:23: warning: comparison of integer expressions of different signedness: ‘int’ and ‘uint’ {aka ‘unsigned int’} [-Wsign-compare]
   20 |         for (int j=0;j<m;j++){
      |                      ~^~