C语言程序设计参考答案

《C语言程序设计》实验四从键盘上输入一个整数n，输出该数的阶乘n!#include<stdio.h>void main(){int n,i,t=1;printf("请输入整数n:");scanf("%d",&n);for(i=1;i<=n;i++)t=i*t;printf("%d",t);}求1！＋2！＋……＋n!#include<stdio.h>void main(){int n,i,t=1,sum=0;printf("请输入整数n:");scanf("%d",&n);for(i=1;i<=n;i++){t=i*t;sum=sum+t;}printf("%d",sum);}编程求出从公元元年到今天，总共经过了多少天，多少星期零几天；#include<stdio.h>void main(){int year,month,day;int t=0,i,j,week;printf("请输入年份:");scanf("%d",&year);printf("请输入月份:");scanf("%d",&month);printf("请输入月份:");scanf("%d",&day);for(i=1;i<year;i++)if(year%4==0&&year%100!=0||year%400==0)t=t+366;elset+=365;for(j=1;j<month;j++)if(j==1||j==3||j==5||j==7||j==8||j==10||j==12)t=t+31;else{if(j==2){if(year%4==0&&year%100!=0||year%400==0)t=t+29;elset=t+28;}elset=t+30;}t=t+day;week=t/7;day=t%7;printf("%d\n",t);printf("%5d% d",week,day);}编程输出所有100000以内的回文数#include<stdio.h>void main(){int n,i=0;for(n=10;n<100000;n++)if(n%10==n/10||n/100==n%10||n/1000==n%10&&n/100%10==n%100/10||n/1 0000==n%10&&n/1000%10==n/10%10)if(n%10!=0){printf("%6d",n);i++;}printf("\n");printf("%d",i);}e＝1＋1/1！＋1/2！＋1/3！＋……＋1/n！#include<stdio.h>void main(){int n,i,t=1;double e=1.0;printf("请输入整数n:");scanf("%d",&n);for(i=1;i<=n;i++){t=i*t;e+=1.0/t;}printf("1+1/1!+1/2!+...+1/n!=%lf",e);}《C语言程序设计》实验五编程输出10～20000之间的所有质数，并统计其个数#include<stdio.h>void main(){int n,i,j=0;for(n=10;n<20000;n++){for(i=2;i<n;i++){if(n%i==0)break;}if(i>=n){printf("%6d",n);j++;}}printf("\n%d",j);}编程按以下形式输出九九乘法表；1*1=1 2*1=2 3*1=3 4*1=4 5*1=5 6*1=6 7*1=7 8*1=8 9*1=9 2*2=4 3*2=6 4*2=8 5*2=10 6*2=12 7*2=14 8*2=16 9*2=18 3*3=9 4*3=12 5*3=15 6*3=18 7*3=21 8*3=24 9*3=27 4*4=16 5*4=20 6*4=24 7*4=28 8*4=32 9*4=36 5*5=25 6*5=30 7*5=35 8*5=40 9*5=45 6*6=36 7*6=42 8*6=48 9*6=54 7*7=49 8*7=56 9*7=63 8*8=64 9*8=72 9*9=81#include<stdio.h>void main(){int i,j,k;for(i=1;i<=9;i++){for(j=1;j<=9;j++)if(j>=i)printf("%d*%d=%-4d",j,i,i*j);printf("\n");for(k=1;k<=i;k++)printf(" ");}printf("\n");}用0～9可以组成多少个没有重复数字的三位偶数#include<stdio.h>void main(){int i,gw,sw,bw,count=0;for(i=100;i<=999;i++){gw=i%10;sw=i/10%10;bw=i/100;if(gw!=sw&&sw!=bw)if(i%2==0){printf("%4d",i); count++;}}printf("\n");printf("共有%d个没有重复数字的三位偶数\n",count);}从键盘输入一个数，将之进行因式分解；（如输入8，则8＝1×2×4）#include<stdio.h>void main(){int n,i;printf("请输入一个整数");scanf("%d",&n);printf("1*");for(i=2;i<=n;i++){while(n!=i){if(n%i==0){printf("%d*",i);n=n/i;}else break;}}printf("%d",n);}从键盘上输入一个数，将之插入到一个有序的数组中#include <stdio.h>void main(){int a[6]={1,3,6,8,9};int i,n;printf("请输入一个数");scanf("%d",&n);for(i=4;i>=0&&a[i]>n;){a[i+1]=a[i];i--;}a[++i]=n;for(i=0;i<6;i++){ printf("a[%d]=%d ",i,a[i]);printf("\n");}}《C语言程序设计》实验六编程输出3×4的二维数组中的最大值、最小值及其所在的行列；# include<stdio.h>void main(){int a[3][4]={1,3,5,7,9,4,2,11,16,14,13,15};int i,j,max,row,col,min;max=a[0][0];min=a[0][0];for(i=0;i<3;i++){for(j=0;j<4;j++)if(a[i][j]>max)max=a[i][j];row=i;col=j;}printf("%d\n%d\n%d\n",max,row,col);row=0;col=0;if(min>a[i][j]){min=a[i][j];row=i;col=j;}printf("%d\n%d\n%d",min,row,col);}用冒泡排序法对一个有10个元素的数组进行降序排序。

#include<stdio.h>void main(){int i,j,t;int a[10]={2,4,3,6,8,19,7,5,0,1};for(j=0;j<9;j++)for(i=0;i<9-j;i++)if(a[i]<a[i+1]){t=a[i];a[i]=a[i+1];a[i+1]=t;}for(i=0;i<10;i++)printf("%2d",a[i]);}编程实现两个字符串的连接#include<string.h>void main(){char a[30],b[30];int i,n;gets(a);gets(b);n=strlen(a);for(i=0;b[i];i++)a[n++]=b[i];a[n]='\0';puts(a);}编程实现两个字符串的比较#include<stdio.h>void main(){char a[81],b[81],c;int i;gets(a);gets(b);for(i=0;a[i]==b[i]&&a[i];i++);c=a[i]-b[i];printf("%d",c);}《C语言程序设计》实验七编程用指针输出3×4的二维数组中的所有元素及最大值；void main(){int a[3][4]={{0,1,2,3},{4,5,6,7},{9,10,11,12}},*p;int max=a[0][0],i,j;p=&a[0][0];for(i=0;i<3;i++)for(j=0;j<4;j++)printf("%3d",*(*(a+i)+j));printf("\n");for(i=0;i<3;i++)for(j=0;j<4;j++)if(max<*(*(a+i)+j))max=*(*(a+i)+j);printf("%d",max);}编程用指针实现：从键盘输入一个字符串，将之逆序后输出；#include<stdio.h>#include<string.h>void main(){char a[81],*p;int len,i,t;p=a;printf("请输入字符串a:");gets(a);len=strlen(a);for(i=0;i<len/2;i++){t=*(p+i);*(p+i)=*(p+len-i-1);*(p+len-i-1)=t;}puts(a);}从键盘上输入一个字符串，判断该串是否为回文串，如果是回文，则输出1，否则输出0。