Compilare: user.cpp: In function ‘int main()’: user.cpp:12:17: warning: unused variable ‘l’ [-Wunused-variable] char *p;int l = strlen(s) * 2; ^ user.cpp:8:35: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("beep.in", "r", stdin); ^ user.cpp:9:37: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("beep.out", "w", stdout); ^ user.cpp:10:24: warning: ignoring return value of ‘char* fgets(char*, int, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] fgets(s,1005,stdin); ^ user.cpp:11:25: warning: ignoring return value of ‘char* fgets(char*, int, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] fgets(s1,1005,stdin); ^