Compilare: main.cpp: In function 'void dfs1(int, int)': main.cpp:119:19: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i = 0;i < adj[n].size();i++) { ~~^~~~~~~~~~~~~~~ main.cpp: In function 'void dfs2(int, int)': main.cpp:129:19: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i = 0;i < adj[n].size();i++) if(adj[n][i].to != p) st.upd(hm[adj[n][i].to], hs, ht[adj[n][i].to]); ~~^~~~~~~~~~~~~~~ main.cpp:130:19: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i = 0;i < adj[n].size();i++) { ~~^~~~~~~~~~~~~~~ main.cpp:136:19: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i = 0;i < adj[n].size();i++) if(adj[n][i].to != p) st.upd(hm[adj[n][i].to], hs, -ht[adj[n][i].to]); ~~^~~~~~~~~~~~~~~ main.cpp: In function 'int main()': main.cpp:141:32: warning: ignoring return value of 'int fscanf(FILE*, const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] fscanf(input, "%d%d", &N, &H); ^ main.cpp:143:40: warning: ignoring return value of 'int fscanf(FILE*, const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] fscanf(input, "%d%d%d", &u, &v, &w); ^