Compilare: main.cpp: In function 'int main()': main.cpp:27:22: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (j = 0 ; j < m[s].size() ; j++ ) { ~~^~~~~~~~~~~~~ main.cpp:20:27: warning: ignoring return value of 'int fscanf(FILE*, const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] fscanf (fin, "%d", &n ) ; ^ main.cpp:22:32: warning: ignoring return value of 'int fscanf(FILE*, const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] fscanf (fin, "%d", &v[i] ) ; ^