Compilare: main.cpp: In function 'bool is_hash(int, int)': main.cpp:21:18: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i=0;i<H[s].size();i++) { ~^~~~~~~~~~~~ main.cpp: In function 'int main()': main.cpp:42:26: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int j = 0; j < Graph[i].size(); j++) { ~~^~~~~~~~~~~~~~~~~ main.cpp:30:28: warning: ignoring return value of 'int fscanf(FILE*, const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] fscanf(IN,"%d%d",&P,&N); ^ main.cpp:33:27: warning: ignoring return value of 'int fscanf(FILE*, const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] fscanf(IN,"%d",&K); ^ main.cpp:35:31: warning: ignoring return value of 'int fscanf(FILE*, const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] fscanf(IN,"%d",&X); ^