Compilare: user.cpp: In function ‘int main()’: user.cpp:83:33: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(i = 0; i < strlen(s1); ++ i) ^ user.cpp:90:33: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(i = 0; i < strlen(s2); ++ i) ^ user.cpp:69:36: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("logic.in", "r", stdin); ^ user.cpp:70:37: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("logic.out","w", stdout); ^ user.cpp:71:22: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d\n", &n); ^ user.cpp:81:17: warning: ignoring return value of ‘char* gets(char*)’, declared with attribute warn_unused_result [-Wunused-result] gets(s1); ^ user.cpp:82:17: warning: ignoring return value of ‘char* gets(char*)’, declared with attribute warn_unused_result [-Wunused-result] gets(s2); ^ user.cpp: In function ‘int fact2(char*, int)’: user.cpp:64:17: warning: ‘val’ may be used uninitialized in this function [-Wmaybe-uninitialized] return semn * val; ^ user.cpp:64:17: warning: ‘semn’ may be used uninitialized in this function [-Wmaybe-uninitialized] /tmp/ccAUk34J.o: In function `main': user.cpp:(.text.startup+0x15e): warning: the `gets' function is dangerous and should not be used.