Question

有一行电文，已按规律译成密码。即将字母变成其后第二个字母（a变成c,b变成d,c变成e,…,x变成z,y变成a,z变

Answer 1

#include<stdio.h>
void main()
{
char str[80];
int i;
printf("Input a line:");
scanf("%s",str);
for(i=0;i!=80;i++)
{
if(str[i]=='\n')break;
if((str[i]>='a')&&(str[i]<='z')||(str[i]>='A')&&(str[i]<='Z'))
{
str[i]=str[i]+2;
if((str[i]>'z')&&(str[i]<='z'+2)||(str[i]>'Z')&&(str[i]<='Z'+2))
str[i]-=26;
}
}
printf("%s\n",str);
}

Answer 2

#include <stdio.h>
#include <string.h>
void main()
{
unsigned int i;
char p[80];
printf ("请输入密文:");
scanf ("%s",p);
i=0;
while(i<strlen(p))
{
if(*(p+i)<0x79) *(p+i)+=2;
else *(p+i)-=24;

printf("%c",*(p+i));
i++;
}
printf("\n");
}