Compilare: main.cpp: In function 'int main()': main.cpp:18:29: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result] freopen(iname,"r",stdin); ^ main.cpp:19:30: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result] freopen(oname,"w",stdout); ^ main.cpp:20:21: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] scanf("%d\n",&t); ^ main.cpp:23:33: warning: ignoring return value of 'char* fgets(char*, int, FILE*)', declared with attribute warn_unused_result [-Wunused-result] fgets(s,sizeof(s),stdin); ^