Compilare: main.cpp: In function 'int main()': main.cpp:154:20: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i = 0; i < paths.size(); i++) { ~~^~~~~~~~~~~~~~ main.cpp:159:22: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int j = 0; j < paths[i].size(); j++) ~~^~~~~~~~~~~~~~~~~ main.cpp:138:38: 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:139:40: 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:141:25: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] scanf("%d %d", &n, &m); ^ main.cpp:143:25: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] scanf("%d", &val[i]); ^ main.cpp:146:27: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] scanf("%d %d", &x, &y); ^ main.cpp:165:34: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] scanf("%d %d %d", &t, &x, &y); ^