transposition.cpp

本人自行编写的替换密码小程序,程序不大,是作为试验的

#include<stdio.h>
#include<string.h>
#include<stdlib.h>

void main()
{
	char str[]="cryptography";
    int i,key;  
	char *ciphe;
	ciphe=(char*)malloc(strlen(str));
	puts("the plaintext is :\n");
	puts(str);
	printf("\nnow assign the key number:\n");    
	scanf("%d",&key);
	for(i=0;i<strlen(str);i++)
	ciphe[i]=str[i]+key;
	puts("\nthe encrypted text is :\n");
	for(i=0;i<strlen(ciphe);i++)
		printf("%c",ciphe[i]);
	printf("\n");
	
}