playfair_function.h

vc++实现des算法

#include "string.h"
#include "iostream.h"
#include "stdio.h"
char str_playfair[27]="abcdefghiklmnopqrstuvwxyz";
char sec_matrix[5][5];
char sec_playfair[27];
int x,y;
void find_playfairnode(char st);
void secr_playfair(char a[27]);
void find_playfairnode(char st)
{
	int i,k,j;
	for(i=0;i<5;i++)
		for(j=0;j<5;j++)
	{
		if(st==sec_matrix[i][j])
		{
			x=i;
			y=j;
			break;
		}

	}
}

void secr_playfair(char a[27])
{
	int i,j,k,l,m;
	i=strlen(a);
	for(j=0;j<i;j++)
	{
		if(a[j]=='j') continue;
		k=strlen(sec_playfair);
		for(l=0;l<k;l++)
		{
			if(sec_playfair[l]==a[j])
			break;
		}
		if(l>=k)
		{for(m=0;sec_playfair[m]!='\0';m++);sec_playfair[m]=a[j];}
	}

	for(k=0;sec_playfair[k]!='\0';k++);
	for(i=0;str_playfair[i]!='\0';i++)
	{
			k=strlen(sec_playfair);
		for(l=0;l<k;l++)
		{
				if(sec_playfair[l]==str_playfair[i])
				break;
		}
		if(l>=k)
		{for(m=0;sec_playfair[m]!='\0';m++);
		sec_playfair[m]=str_playfair[i];}
		
	}
}