Compilare: main.cpp: In function 'int main()': main.cpp:24:28: warning: NULL used in arithmetic [-Wpointer-arith] for(int i = 0; s[i] != NULL; i++) ^~~~ main.cpp:34:39: warning: NULL used in arithmetic [-Wpointer-arith] for(i = 0; sum + 3 < w && s[i] != NULL; i++) ^~~~ main.cpp:41:16: warning: NULL used in arithmetic [-Wpointer-arith] if(s[i] != NULL) ^~~~ main.cpp:17:37: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result] freopen("texttrim.in","r",stdin); ^ main.cpp:18:39: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result] freopen("texttrim.out","w",stdout); ^