簡單的C回顧

#include <stdio.h>

int main(){

    int a = 10;
    printf("%d\n",a);
    scanf("%d",&a);
    printf("%d",a);
    float b = 11;
    printf("%f\n", b);
    char* s = "hello world!\n";
    printf("%s", s);
    return 0;
}