很不安全的加密
#include<stdio.h>
#include<string.h>
void encrypt(char *base,int shift)
{
unsigned length = strlen(base);
unsigned index;
if(shift>0)
{
for(index=0;index<length;index++)
{
if(base[index]>='a'&&base[index]<='z')base[index]=(base[index]+shift-'a')%26+'a';
else if(base[index]>='A'&&base[index]<='Z')base[index]=(base[index]+shift-'A')%26+'A';
else ;
}
}
else if(shift<0)
{
for(index=0;