Compilare: main.cpp: In function 'void bfs(int)': main.cpp:19:13: warning: unused variable 'k' [-Wunused-variable] int l = 1, k; ^ main.cpp: In function 'int main()': main.cpp:38:31: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result] freopen("bfs.in", "r", stdin); ^ main.cpp:39:33: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result] freopen("bfs.out", "w", stdout); ^ main.cpp:41:31: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] scanf("%d %d %d", &n, &m, &s); ^ main.cpp:45:25: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] scanf("%d %d", &x, &y); ^