Compilare: main.cpp: In function 'void dfs(int, int)': main.cpp:26:23: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int i = 0; i < sons[nod].size(); ++ i) ~~^~~~~~~~~~~~~~~~~~ main.cpp:38:31: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int j = 0; j < sons[nod].size(); ++ j) ~~^~~~~~~~~~~~~~~~~~ main.cpp: In function 'int main()': main.cpp:53:26: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] scanf("%d%d", &n, &k); ^ main.cpp:57:30: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] scanf("%d%d", &u, &v); ^ main.cpp:72:30: warning: 'root' may be used uninitialized in this function [-Wmaybe-uninitialized] printf("%d\n", dp[root][1] % mod); ~~~~~~~~~~^