Compilare: main.cpp: In function 'void dfs1(int)': main.cpp:72:9: warning: unused variable 't1' [-Wunused-variable] int t1 = Heavy_Edge[nod]; ^~ main.cpp: In function 'int answer(int, int)': main.cpp:78:9: warning: unused variable 'val' [-Wunused-variable] int val = 0 ; ^~~ main.cpp: In function 'int main()': main.cpp:97:25: warning: unused variable 'op' [-Wunused-variable] int q , i , x , y, op; ^~ main.cpp: In function 'char read_ch()': main.cpp:19:35: warning: ignoring return value of 'size_t fread(void*, size_t, size_t, FILE*)', declared with attribute warn_unused_result [-Wunused-result] fread(_in_buff, 1, 32768, stdin); ^ main.cpp: In function 'int main()': main.cpp:95:32: 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:96:34: 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); ^