Compilare: main.cpp: In function 'int main()': main.cpp:25:28: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (k = 0 ; k < p[v[i]].size() ; k++){ ~~^~~~~~~~~~~~~~~~ main.cpp:15:25: warning: ignoring return value of 'int fscanf(FILE*, const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] fscanf (fin,"%d",&n); ^ main.cpp:17:32: warning: ignoring return value of 'int fscanf(FILE*, const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] fscanf (fin,"%d",&v[i]); ^