⑴ 如何使用c語言編寫一個密碼程序
密碼保存在文件中,從文件中讀取密碼,但是沒做容錯和異常處理,僅供參考
#include <stdio.h>
#include <string.h>
#define PSDLEN 6
void inputPsd(char *str) /*處理輸入*/
{
int i;
for(i = 0; i < PSDLEN; i++)
{
while(1)
{
str[i] = getch();
if(str[i] == '\b') /*處理退格鍵*/
{
i--;
if(i < 0)
{
i = 0;
}
else
{
printf("\b \b");
}
continue;
}
else if(str[i] == '\r') /*處理回車鍵*/
{
continue;
}
else
{
printf("*");
break;
}
}
}
str[i] = '\0';
printf("\n");
}
int checkFirst() /*檢測是否是第一次使用*/
{
FILE *fp;
if((fp = fopen("psd.dat", "rb")) == NULL)
{
return 1;
}
fclose(fp);
return 0;
}
void firstUse() /*第一次使用 需要輸入密碼*/
{
FILE *fp;
int i;
char passwd[PSDLEN + 1];
char checkPsd[PSDLEN + 1];
if((fp = fopen("psd.dat", "wb")) == NULL)
{
printf("Creat password error!\n");
exit(1);
}
while(1)
{
printf("Please input password:");
inputPsd(passwd);
printf("\nPlease input password again:");
inputPsd(checkPsd);
if(!strcmp(passwd, checkPsd))
{
break;
}
printf("\ncheck password error! \n");
}
fwrite(passwd, sizeof(char), PSDLEN, fp);
fclose(fp);
}
void login() /*核對密碼,並登錄*/
{
FILE *fp;
int i, num = 3;
char passwd[PSDLEN + 1];
char checkPsd[PSDLEN + 1];
if((fp = fopen("psd.dat", "rb")) == NULL)
{
puts("Open psd.dat error");
exit(1);
}
fread(passwd, sizeof(char), PSDLEN, fp);
fclose(fp);
passwd[PSDLEN] = '\0';
printf("Please input password to login");
while(num)
{
printf("you have %d chances to cry:\n", num);
inputPsd(checkPsd);
if(!strcmp(passwd, checkPsd))
{
break;
}
puts("\npassword error,Please input again");
num--;
}
if(!num)
{
puts("Press any key to exit...");
getch();
exit(0);
}
else
{
puts("\n--------\nWelcome!\n--------\n");
}
}
void main()
{
if(checkFirst())
{
firstUse();
}
else
login();
getch();
}
⑵ 如何用C語言編寫密碼程序
1、用一個字元數組來存密碼
再用一個字元數組接收你的輸入,然後用strcmp
來比較,如果返回0則密碼是正確的
2、常式:
#include"stdio.h"
#include"string.h"
intmain()
{
charmima[100]="YuanShi888";
charinput[100]={0};
printf("請輸入密碼:");
gets(input);
if(strcmp(mima,input)==0)
printf("恭喜你,密碼正確! ");
else
printf("對不起,密碼輸入錯誤! ");
}
⑶ 用c語言生成八位的隨機密碼
#include<stdio.h>
#include<stdlib.h>
#include<time.h>
int main()
{
char pool[]=
{
Ɔ',Ƈ',ƈ',Ɖ',Ɗ',Ƌ',ƌ',ƍ',Ǝ',Ə',
'a','b','c','d','e','f','g','h','i','j',
'k','l','m','n','o','p','q','r','s','t',
'u','v','w','x','y','z','A','B','C','D',
'E','F','G','H','I','J','K','L','M','N',
'O','P','Q','R','S','T','U','V','W','X',
'Y','Z'
};//隨機池
srand(time(0));
char pwd[9];
pwd[8]='