Question

1、编程要求输入一个五位数，输出它的各个数位上数字之和。

2、编程将“China”译成密码。密码规律是：用原来字母后面的第三个字母代替原来的字母。

Answer 1

#include <stdio.h>

void fun()
{
char szBuff[128] = "China";
int i = 0;

printf("输入字符串：%s\n", szBuff);
for (; szBuff[i] != 0; ++i)
{
szBuff[i] += 3;
}
printf("输出字符串：%s\n", szBuff);
}

int main(void)
{
int i;
int a = 0;

printf("输入一个数字：");
scanf("%d", &i);
while(i)
{
a += i % 10;
i /= 10;
}
printf("各个位相加等于：%d\n", a);

fun();

return 0;
}

Answer 2

1、
#include <stdio.h>
#include <string.h>
#include <math.h>

int f(int x)
{
int sum=0;
while(x > 0){
sum += x%10;
x = x/10;
}
return sum;
}

void main()
{
int x;
printf("输入一个5位正整数\n");
scanf("%d",&x);
printf("和是%d\n",f(x));
}

2、
#include <stdio.h>
#include <string.h>
#include <math.h>

void main()
{
char buf[] = "China";
int i;
for (i=0; i<strlen(buf); i++)
{
buf[i] += 3;
}

printf("加密后为：%s\n", buf);
}

Answer 3

//第一题
123
sum=6
Press any key to continue

#include <stdio.h>
#include <stdlib.h>
main()
{
int i=0,sum=0;
char str[100]="\0";
gets(str);
while (str[i]!='\0')
sum+=str[i++]-'0';
printf("sum=%d\n",sum);
}

第二题

Fklqd
Press any key to continue

#include <stdio.h>
main()
{
int i=0,sum=0;
char str[]="China";
while (str[i]!='\0')
{
str[i]=str[i]+3;
printf("%c",str[i++]);
}
printf("\n");
}

Answer 4

#include<stdio.h>

void main(void)
{
int i,num,sum=0;

printf("input your number\n");
scanf("%d",&num);

for(i=0;i<5;i++)
{

sum+=num%10;
num=num/10;
}

printf("%d",sum);
}第一题