请指点指点???
main(){int score,mark;
printf("Enter score:");
scanf("%d",&score);
mark=-1;
if(score>=0&&score<=100)
mark=score/10;
switch(mark)
{case 10:
case 9:printf("Very good\n");break;
case 8:printf("Good\n");break;
case 7:
case 6:printf("Passed\n");break;
case 5:
case 4:
case 3:
case 2:
case 1:
case 0:printf("failed\n");break;
default:printf("Enter error!\n");
}
}
mark为什么要赋值,mark=-1是什么意思?