Compilare: main.cpp: In function 'bool check(int, int, int)': main.cpp:132:19: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int p = 0; p < pfs[i].size(); p++){ ~~^~~~~~~~~~~~~~~ main.cpp: In function 'int main()': main.cpp:141:35: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result] freopen("deletegcd.in","r",stdin); ^ main.cpp:142:37: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result] freopen("deletegcd.out","w",stdout); ^ main.cpp:143:10: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] ri2(n,q); ^ main.cpp:146:8: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] ri(x); ^ main.cpp:159:11: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] ri2(l,r); ^