1. 将“We are students.”这个英文词句用k=4的凯萨密码翻译成密码
1. 恺撒密码，
作为一种最为古老的对称加密体制，他的基本思想是：
通过把字母移动一定的位数来实现加密和解密。
例如，如果密匙是把明文字母的位数向后移动三位，那么明文字母B就变成了密文的E，依次类推，X将变成A,Y变成B,Z变成C，由此可见，位数就是凯撒密码加密和解密的密钥。
如：ZHDUHVWXGHQWV（后移三位）
2. 凯撒密码，
是计算机C语言编程实现加密和解密。挺复杂的。你可以研究一下哦。
2. 将凯撒密码（K=7）的加密、解密过程用C语言编程实现
#include<stdio.h>
#include<ctype.h>
#define maxlen 100
#define K 7
char *KaisaEncode(char *str)//加密
{
char *d0;
d0=str;
for(;*str!=' ';str++)
{
if(isupper(*str))
*str=(*str-'A'+K)%26+'A';
else if(islower(*str))
*str=(*str-'a'+K)%26+'a';
else
continue;
}
return d0;
}
char *KaisaDecode(char *str)//解密
{
char *d0;
d0=str;
for(;*str!=' ';str++)
{
if(isupper(*str))
*str=(*str-'A'-K+26)%26+'A';
else if(islower(*str))
*str=(*str-'a'-K+26)%26+'a';
else
continue;
}
return d0;
}
int main(void)
{
char s[maxlen];
gets(s);
puts(KaisaEncode(s));
puts(KaisaDecode(s));
return 0;
}
3. 将凯撒密码X的加密、解密过程用C语言编程实现
(2)kaiser加密算法 具体程序：#include#include char encrypt(char ch,int n) { while(ch>='A'&&ch<='z') {="" return="" ('a'+(ch-'a'+n)%26);="" }="" while(ch="">='a'&&ch<='z') {="" return="" ('a'+(ch-'a'+n)%26);="" }="" return="" ch;="" }="" void="" menu（)="" {="" clrscr();="" printf("n="========================================================");" printf("n1.encrypt="" the="" file");="" printf("n2.decrypt="" the="" file");="" printf("n3.force="" decrypt="" file");="" printf("n4.quitn");="" printf("="========================================================n");" printf("please="" select="" a="" item:");="" return;="" }="" main()="" {="" int="" i,n;="" char="" ch0,ch1;="" file="" *in,*out;="" char="" infile[20],outfile[20];="" textbackground(black);="" textcolor(lightgreen);="" clrscr();="" sleep(3)；="" menu();="" ch0="getch();" while(ch0!='4' )="" {="" if(ch0="='1')" {="" clrscr();="" printf("nplease="" input="" the="" infile:");="" scanf("%s",infile)；="" if((in="fopen(infile,"r"))==NULL)" {="" printf("can="" not="" open="" the="" infile!n");="" printf("press="" any="" key="" to="" exit!n");="" getch();="" exit(0);="" }="" printf("please="" input="" the="" key:");="" scanf("%d",&n)；="" printf("please="" input="" the="" outfile:");="" scanf("%s",outfile)；="" if((out="fopen(outfile,"w"))==NULL)" {="" printf("can="" not="" open="" the="" outfile!n");="" printf("press="" any="" key="" to="" exit!n");="" fclose(in);="" getch();="" exit(0);="" }="" while(!feof(in)）="" {="" fputc(encrypt(fgetc(in),n),out);="" }="" printf("nencrypt="" is="" over!n");="" fclose(in);="" fclose(out);="" sleep(1);="" }="" if(ch0="='2')" {="" clrscr();="" printf("nplease="" input="" the="" infile:");="" scanf("%s",infile)；="" if((in="fopen(infile,"r"))==NULL)" {="" printf("can="" not="" open="" the="" infile!n");="" printf("press="" any="" key="" to="" exit!n");="" getch();="" exit(0);="" }="" printf("please="" input="" the="" key:");="" scanf("%d",&n)；="" n="26-n;" printf("please="" input="" the="" outfile:");="" scanf("%s",outfile)；="" if((out="fopen(outfile,"w"))==NULL)" {="" printf("can="" not="" open="" the="" outfile!n");="" printf("press="" any="" key="" to="" exit!n");="" fclose(in);="" getch();="" exit(0);="" }="" while(!feof(in))="" {="" fputc(encrypt(fgetc(in),n),out);="" }="" printf("ndecrypt="" is="" over!n");="" fclose(in);="" fclose(out);="" sleep(1);="" }="" if(ch0="='3')" {="" clrscr();="" printf("nplease="" input="" the="" infile:");="" scanf("%s",infile)；="" if((in="fopen(infile,"r"))==NULL)" {="" printf("can="" not="" open="" the="" infile!n");="" printf("press="" any="" key="" to="" exit!n");="" getch();="" exit(0);="" }="" printf("please="" input="" the="" outfile:");="" scanf("%s",outfile)；="" if((out="fopen(outfile,"w"))==NULL)" {="" printf("can="" not="" open="" the="" outfile!n");="" printf("press="" any="" key="" to="" exit!n");="" fclose(in);="" getch();="" exit(0);="" }="" for(i=""><=25;i++) 暴力破解过程，在察看信息正确后，可以按'q'或者'q'退出*/="" {="" rewind(in);="" rewind(out);="" clrscr();="" printf("="=========================================================n");" printf("the="" outfile="" is:n");="" printf("="=========================================================n");" while(!feof(in))="" {="" ch1="encrypt(fgetc(in),26-i);" putch(ch1);="" fputc(ch1,out);="" }="" printf("n="=======================================================n");" printf("the="" current="" key="" is:="" %d="" n",i)；="" printf("press="" 'q'="" to="" quit="" and="" other="" key="" to="">n"); printf("==========================================================n"); ch1=getch(); if(ch1=='q'||ch1=='Q') { clrscr(); printf("nGood Bye!n"); fclose(in); fclose(out); sleep(3); exit(0); } } printf("nForce decrypt is over!n"); fclose(in); fclose(out); sleep(1); } menu(); ch0=getch(); } clrscr(); printf("nGood Bye!n"); sleep(3); }。
4. 怎样编写程序：实现恺撒密码加密单词"julus"
用下面程序：新建个txt，放进去任意单词，设置#define N 5中的值，实现字母移位，达到加密目的。
本程序提供解密功能#include #define N 5void jiami(char namea[256]) { FILE *fp_jiami,*fp_file2; char c; fp_jiami=fopen(namea,"rb"); fp_file2=fopen("file2.txt","wb"); while(EOF!=(fscanf(fp_jiami,"%c",&c))) { if((c>='A'&&c<='z')||(c>='a'&&c<='z')) {="" c="c+N;" if="" (!((c="">='A'&&c<='z')||(c>='a'&&c<='z')))c=c-26; if(c="">='a'&&c<='z')c=c-32; }="" fprintf(fp_file2,"%c",c);="" }="" fclose(fp_file2);="" fclose(fp_jiami);="" }="" void="" jiemi(char="" en_name[256])="" {="" file="" *fp_jiemi,*fp_file3;="" char="" c;="" fp_jiemi="fopen(en_name,"rb");" fp_file3="fopen("file3.txt","wb");" while(eof!="(fscanf(fp_jiemi,"%c",&c)))" {="" if((c="">='A'&&c<='z')||(c>='a'&&c<='z')) {="" c="c-N;" if="" (!((c="">='A'&&c<='z')||(c>='a'&&c<='z')))c=c+26; if(c="">='A'&&c<='z')c=c+32; }="" fprintf(fp_file3,"%c",c);="" }="" fclose(fp_file3);="" fclose(fp_jiemi);="" }int="" main(){="" char="" name[256];="" int="" n;="" printf（"输入你要操作的txt文本："）；="" gets(name);="" printf("n请选择需要进行的操作：n");="" printf("="" 1：加密="" 2：解密="" n");="" printf（"输入你的选择："）；="" scanf("%d",&n);="" switch(n)="" {="" case="" 1:{jiami(name);printf("t加密成功！！nn");="" break;}="" case="" 2:{jiemi(name);printf("t解密成功！！nn");="" break;}="" default:{printf（"输入操作不存在！"）；}="" }="" return="">
5. 谁有PYTHON编写的凯撒密码的加密和解密代码
给你写了一个.
def convert(c, key, start = 'a', n = 26):
a = ord(start)
offset = ((ord(c) - a + key)%n)
return chr(a + offset)
def caesarEncode(s, key):
o = ""
for c in s:
if c.islower():
o+= convert(c, key, 'a')
elif c.isupper():
o+= convert(c, key, 'A')
else:
o+= c
return o
def caesarDecode(s, key):
return caesarEncode(s, -key)
if __name__ == '__main__':
key = 3
s = 'Hello world!'
e = caesarEncode(s, key)
d = caesarDecode(e, key)
print e
print d
运行结果：
Khoor zruog!
Hello world!
