急求C语言程序A到B只和答:1 include <stdio.h> void main(){ int a,b,sum=0,i;scanf("%d%d",&a,&b);for(i=a;i<=b;i++)sum+=i;printf("%d\n",sum);} 2 include<stdio.h> void main(){ double x, root;int n;double fun(int n,double x);printf("Input x,n:");scanf("%lf%d",&x,&n);r...