C语言编程: 输入20名学生的分数,统计各分数段分布人数,答:include"stdio.h"main(){int x,a,b,c,d,i;a=b=c=d=0;for(i=1;i<=20;i++){scanf("%d",&x);switch(x/10){case 10:case 9:case 8:a++;case 7:b++;case 6:c++;default:d++;} } printf("0-59: %d\n",d);printf("60-69: %d\n",c);printf("70-79: %d\n",b...