Compilare: user.cpp: In function ‘int main()’: user.cpp:28:20: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(;i<strlen(s);i++) ^ user.cpp:36:36: warning: operation on ‘i’ may be undefined [-Wsequence-point] c[i]=s[i++]; ^ user.cpp:11:35: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("text.in", "r", stdin); ^ user.cpp:12:37: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("text.out", "w", stdout); ^ user.cpp:22:16: warning: ‘x’ may be used uninitialized in this function [-Wmaybe-uninitialized] s[strlen(s)-x]='\0'; ^