Compilare: main.cpp: In function 'int main()': main.cpp:197:24: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (j = 0 ; j < vv[i].size() ; j++){ ~~^~~~~~~~~~~~~~ main.cpp:128:29: warning: ignoring return value of 'int fscanf(FILE*, const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] fscanf (fin,"%lld\n",&n); ^