Compilare: main.cpp: In function 'void dfs(int)': main.cpp:23:18: 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 rmq()': main.cpp:40:53: warning: suggest parentheses around '-' inside '<<' [-Wparentheses] if(depth[d[p-1][i]]<depth[d[p-1][i+(1<<p-1)]]) ~^~ main.cpp:43:39: warning: suggest parentheses around '-' inside '<<' [-Wparentheses] d[p][i]=d[p-1][i+(1<<p-1)]; ~^~ main.cpp: In function 'int main()': main.cpp:62:34: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result] freopen("lca.in", "r", stdin); ^ main.cpp:63:36: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result] freopen("lca.out", "w", stdout); ^ main.cpp:66:26: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] scanf("%d%d", &n, &m); ^ main.cpp:70:24: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] scanf("%d", &x); ^ main.cpp:80:30: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] scanf("%d%d", &x, &y); ^