Compilare: main.cpp: In function 'int main()': main.cpp:30:44: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int k = 0 ; k < G[i].size() ; ++ k) { ~~^~~~~~~~~~~~~ main.cpp:38:45: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int k = 0 ; k < G[i].size() ; k++) { ~~^~~~~~~~~~~~~ main.cpp:19:44: warning: ignoring return value of 'int fscanf(FILE*, const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] fscanf(in, "%d %d %d", &n, &m, &e) ; ^ main.cpp:21:45: warning: ignoring return value of 'int fscanf(FILE*, const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] fscanf(in, "%d %d", &x, &y) ; ^