Compilare: main.cpp: In function 'int main()': main.cpp:4:33: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result] freopen("pufu.in", "r", stdin); ^ main.cpp:5:35: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result] freopen("pufu.out", "w", stdout); ^ main.cpp:8:18: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] scanf("%d", &t); ^ main.cpp:10:21: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] scanf("%d ", &n); ^ main.cpp:15:7: warning: 'ch' may be used uninitialized in this function [-Wmaybe-uninitialized] if(ch=='a') ^~