如果循环不工作。运行时显示重复cout。

我正在尝试制作一个随机数生成器猜测游戏,它将允许用户选择一个范围。在选择范围后,用户将尝试猜测数字,直到正确为止。我是c++新手,不明白为什么屏幕上有两个cout输出。我是c++新手,不知道为什么。我正在使用visual studio 17。

#include "stdafx.h"
#include <iostream>
#include <time.h>
#include <cstdlib>
using namespace std;



int main()
{
    int userNum;
    char choice;
    int numattempts = 0;
    int randNumber;
    srand(time(0));




cout << "Welcome to the number guessing game\n" << "Please choose what range you want to guess from\n" << " '1' = 0-20\n '2'= 0-50\n '3'= 0-100\n ";
cin >> choice;



if (choice == '1')
{

    randNumber = 0 + rand() % 20;

    cout << "Enter a number between 0 and 20\n";
    cin >> userNum;
    cout << randNumber;


    do {

        if (userNum < randNumber)
        {
            cout << "Number is Higher\n";
            cin >> userNum;
        }

        else if (userNum > randNumber)
        {
            cout << "Number is Lower\n";
            cin >> userNum;
        }

        else (userNum == randNumber);
        {
            cout << "Congrats You got it!\n";

        }

    } while (userNum != randNumber);
}