Compilare: main.cpp: In function 'void dfs(int, int, int)': main.cpp:90:23: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int i = 0; i < aa[st].size(); ++i) { ~~^~~~~~~~~~~~~~~ main.cpp:97:23: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int i = 0; i < aa[st].size(); ++i) ~~^~~~~~~~~~~~~~~ main.cpp:104:21: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int i = 0; i < aint[node].v.size(); ++i) ~~^~~~~~~~~~~~~~~~~~~~~ main.cpp: In function 'int main()': main.cpp:109:36: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result] freopen("colors2.in", "r", stdin); ^ main.cpp:110:38: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result] freopen("colors2.out", "w", stdout); ^ main.cpp:113:18: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] scanf("%d", &T); ^ main.cpp:117:26: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] scanf("%d%d", &n, &m); ^ main.cpp:119:25: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] scanf("%d", &a[i]); ^ main.cpp:123:25: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] scanf("%d", &b[i]); ^ main.cpp:130:47: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] scanf("%d%d", &e[i].first, &e[i].second); ^