Compilare: main.cpp: In function 'void dfs(int)': main.cpp:47:18: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i=0;i<g[start_node].size();i++) ~^~~~~~~~~~~~~~~~~~~~~ main.cpp: In function 'void solve1(int, int)': main.cpp:55:18: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i=0;i<muchii.size();i++) ~^~~~~~~~~~~~~~ main.cpp: In function 'void solve2(int, int)': main.cpp:65:18: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i=0;i<muchii.size();i++) ~^~~~~~~~~~~~~~ main.cpp: In function 'void solve3(int, int)': main.cpp:88:18: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i=0;i<muchii.size();i++) ~^~~~~~~~~~~~~~ main.cpp: In function 'int main()': main.cpp:99:41: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result] freopen("elicoptere.in", "r", stdin); ^ main.cpp:100:43: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result] freopen("elicoptere.out", "w", stdout); ^ main.cpp:103:20: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] scanf("%d", &c); ^ main.cpp:104:26: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] scanf("%d%d", &n, &k); ^ main.cpp:109:60: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] scanf("%d%d%d%d%d%d", &a1, &b1, &a2, &b2, &a3, &b3); ^