Compilare: user.cpp: In function ‘int main(int, char**)’: user.cpp:64:45: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i = 0 ; i < graph[top].size() ; i++) { ^ user.cpp:45:33: warning: ignoring return value of ‘int fscanf(FILE*, const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] fscanf(fin, "%d %d", &N, &M); ^ user.cpp:48:44: warning: ignoring return value of ‘int fscanf(FILE*, const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] fscanf(fin, "%d %d %d", &a, &b, &c); ^