Compilare: user.cpp: In function ‘int mod(int&)’: user.cpp:12:1: warning: no return statement in function returning non-void [-Wreturn-type] } ^ user.cpp: In function ‘void read()’: user.cpp:20:33: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d %d %d\n", &k, &a, &b); ^ user.cpp:21:12: warning: ignoring return value of ‘char* gets(char*)’, declared with attribute warn_unused_result [-Wunused-result] gets(s); ^ user.cpp: In function ‘int main()’: user.cpp:54:33: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("diviz.in", "r", stdin); ^ user.cpp:55:35: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("diviz.out", "w", stdout); ^ /tmp/cccOQuZY.o: In function `read()': user.cpp:(.text+0x6a): warning: the `gets' function is dangerous and should not be used.