Compilare: main.cpp: In function 'void DFS(int, int)': main.cpp:22:19: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (i = 0; i < hashmap[key].size(); i++) { ~~^~~~~~~~~~~~~~~~~~~~~ main.cpp:29:23: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int i = 0; i < arb[nodCrt].size(); i++) { ~~^~~~~~~~~~~~~~~~~~~~ main.cpp: In function 'int main()': main.cpp:38:38: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result] freopen("arbore3.in", "r", stdin); ^ main.cpp:39:40: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result] freopen("arbore3.out", "w", stdout); ^ main.cpp:41:28: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] scanf("%d%d", &n, &sum); ^ main.cpp:43:38: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] scanf("%d%d", &tata, &val[i]); ^