各位大神帮忙看看我这个程序哪里错了?
#include<stdio.h>main()
{
int i,score;
double n;
printf("Please input your score: ");
scanf("%d",&score);
n=score/10;
if(n<6)
i=1;
if(n=6)
i=6;
if(n=7)
i=7;
if(n=8)
i=8;
if(n==9||n==10)
i=9;
switch(i)
{
case 1:printf("Your grade is E");break;
case 6:printf("Your grade is D");break;
case 7:printf("Your grade is C");break;
case 8:printf("Your grade is B");break;
case 9:printf("Your grade is A");break;
default:printf("Wrong number!");
}
return 0;
}