How to compile memo using gcc at cmd?

i’m sorry for my bad English;;
i wrote source code

#include <stdio.h>

int main(void)
  printf("hello world\n");
  return 0;

in memo. i saved it as “hello.c”. and “hello.c” file is stored in C:
i want to compile it using gcc at cmd. gcc is already downloaded in right way. what should i do?