Compilare: user.cpp: In function ‘int main()’: user.cpp:58:29: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d %d\n", &N, &M); ^ user.cpp:60:22: warning: ignoring return value of ‘char* gets(char*)’, declared with attribute warn_unused_result [-Wunused-result] gets(row + 1); ^ /tmp/ccfdiiN8.o: In function `main': user.cpp:(.text.startup+0x5d): warning: the `gets' function is dangerous and should not be used.