加密:
#include<stdio.h>
#include<string.h>
int main(){
//凯撒加密
char enc[100],dec[100];
printf("要加密或者解密的字符串:");
scanf("%s",enc);
printf("输入偏移位数");
int con;
scanf("%d",&con);
int i;
for(i=0;i<strlen(enc);++i){
if(enc[i]<='z'&&enc[i]>='a'){
dec[i] = (enc[i]-'a'+con)%26 + 'a';
}else{
dec[i] = (enc[i]-'A'+con)%26 + 'A';
}
}
dec[i]='\0';
printf("要加密或者解密的字符串:%s",dec);
return 0;
}
解密:
#include<stdio.h>
#include<string.h>
int main(){
//凯撒加密
char enc[100],dec[100];
printf("要加密或者解密的字符串:");
scanf("%s",enc);
printf("输入偏移位数");
int con;
scanf("%d",&con);
int i;
for(i=0;i<strlen(enc);++i){
if(enc[i]<='z'&&enc[i]>='a'){
dec[i] = (enc[i]-'a'+26-con)%26 + 'a';
}else{
dec[i] = (enc[i]-'A'+26-con)%26 + 'A';
}
}
dec[i]='\0';
printf("要加密或者解密的字符串:%s",dec);
return 0;
}