#include <stdio.h>

void main()
{

        int re,n;

        printf("성적을 입력하세요 : ");
        scanf("%d",&re);

        if(re>=90) n=1;
        else if(re>=80&&re<90) n=2;
        else if(re>=70&&re<80) n=3;
        else if(re>=60&&re<70) n=4;
        else if(re<60) n=5;


        switch(n)
        {
        case 1: 
                printf("A \n");
                break;
        case 2: 
                printf("B \n");
                break;
        case 3: 
                printf("C \n");
                break;
        case 4:
                printf("D \n");
                break;
        default:
                printf("F \n");
        }
}

이렇게짰는데...
이거 스위치문만 써서 가능한가요??