C语言:求数列61,122,213,340,509,...前n项的和;n(0<n<=100)由键盘输入...答:代码文本:include "stdio.h"define N 100 int main(int argc,char *argv[]){ int s,n,k,t,i,j;printf("Enter n(int 0<n<=N)...\nn=");if(scanf("%d",&n)==1 && n>0 && n<=N){ for(k=30,j=61,t=61,s=i=0;i<n;s+=t,t+=j,j+=k,k+=6,i++);printf("...
c求输入年月日判断是星期几的一个答:int x,day_code,m,d,s=0,a[12]={31,28,31,30,31,30,31,31,30,31,30,31};scanf("%d",&x);scanf("%d%d",&m,&d);if(m<1||m>13||d>31||d<1)printf("输入错误");else { day_code=(x+(x-1)/4-(x-1)/100+(x-1)/400)%7;for(int i=0;i<m-1;i++)s=s+...