Compilare: main.cpp: In function 'int main()': main.cpp:155:20: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i = 0; i < paths.size(); i++) { ~~^~~~~~~~~~~~~~ main.cpp:160:22: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int j = 0; j < paths[i].size(); j++) ~~^~~~~~~~~~~~~~~~~ main.cpp:139:38: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result] freopen("heavypath.in", "r", stdin); ^ main.cpp:140:40: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result] freopen("heavypath.out", "w", stdout); ^ main.cpp:142:25: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] scanf("%d %d", &n, &m); ^ main.cpp:144:25: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] scanf("%d", &val[i]); ^ main.cpp:147:27: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] scanf("%d %d", &x, &y); ^ main.cpp:166:34: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] scanf("%d %d %d", &t, &x, &y); ^