#include <stdio.h>
#include <iostream>
#define PASSWORD "1234567"
int verify_password(char* password)
{
	int authenticated;
	char buffeer[12];//add local buff to be overflowed
	authenticated=strcmp(password,PASSWORD);
	strcpy(buffer,password);
	return authenticated;
}
void main()
{
    int valid_flag=0;
    char password[1024];
    while(1)
    {
    	printf("please input password: ");
    	scanf("%s",password);
    	valid_flag=verify_password(password);
    	if(valid_flag)
    		printf("incorrect password!\n\n");
    	else
    	{
    		printf("Congratulation! You have passed the verification!\n");
    		break;
    	}
    }
}