序列密码RC4加密算法

#include<stdio.h>
#include<stdlib.h>
#include<string.h>
void swap(unsigned char *s1,unsigned char *s2)
{
char temp;
temp=*s1;
*s1=*s2;
*s2=temp;
}
void re_S(unsigned char *S)
{
unsigned int i;
for(i=0;i<256;i++)
   S[i]=i;
}
void re_T(unsigned char *T,char *key)
{
int i;
int keylen;
keylen=strlen(key);
for(i=0;i<256;i++)
   T[i]=key[i%keylen];
}
void re_Sbox(unsigned char *S,unsigned char *T)
{
int i;
int j=0;
for(i=0;i<256;i++)
{