Compilare: user.cpp: In function ‘int main()’: user.cpp:26:28: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(i=0;i<strlen(s1);i++) ^ user.cpp:7:40: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("parantezare.in","r",stdin); ^ user.cpp:8:42: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("parantezare.out","w",stdout); ^ user.cpp:9:12: warning: ignoring return value of ‘char* gets(char*)’, declared with attribute warn_unused_result [-Wunused-result] gets(s); ^ user.cpp:24:21: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d\n",&m); ^ user.cpp:25:17: warning: ignoring return value of ‘char* gets(char*)’, declared with attribute warn_unused_result [-Wunused-result] gets(s1); ^ /tmp/ccGBUS3C.o: In function `main': user.cpp:(.text.startup+0x55): warning: the `gets' function is dangerous and should not be used.