Is there a way to clear the input in a getline?

Question

I have a countdown timer for a game i'm making. There is a section that asks the player (using getline) if they want to dodge a shot from an enemy except that they only have 3 seconds to decide otherwise the shot will hit them. The problem is that if the player does decide to dodge the shot then whenever I use another getline after that, there will be the number 1 already typed. Is there any way I can clear the number 1 and make it so there is nothing already typed?

This shows the output with a pre-typed number 1

#include <string>
#include <iostream>
#include <thread>
#include <Windows.h>
using namespace std;

string input;

void attack()
{
    getline(cin, input);
}

int main() 
{
    srand(time(NULL));
    int randomIfDodged = ((rand() % 4) + 1);
    ULARGE_INTEGER initialTime;
    ULARGE_INTEGER currentTime;
    FILETIME ft;
    GetSystemTimeAsFileTime(&ft);
    initialTime.LowPart = ft.dwLowDateTime;
    initialTime.HighPart = ft.dwHighDateTime;
    LONGLONG countdownStartTime = 30000000; 
    LONGLONG displayedNumber = 4; 

    while (true)
    {
        GetSystemTimeAsFileTime(&ft);
        currentTime.LowPart = ft.dwLowDateTime;
        currentTime.HighPart = ft.dwHighDateTime;
        bool dodge = false;

        SHORT key = GetKeyState('1');
        if (key & 0x8000)
        {
            dodge = true;
        }
        LONGLONG elapsedTime = currentTime.QuadPart - initialTime.QuadPart;
        LONGLONG currentNumber_100ns = countdownStartTime - elapsedTime;

        if (currentNumber_100ns <= 0)
        {
            system("cls");

            cout << "You took too long, the guard's shot hit you." << endl;
            break;
        }
        if (dodge)
        {
            system("cls");

            if (randomIfDodged <= 2)
            {
                cout << "You dodged the guard's shot!" << endl;
                cout << "What would you like to do now?" << endl;
                attack();
                exit(0);
            }
            else
            {
                cout << "You failed to dodge the guard's shot" << endl;
                attack();
                exit(0);
            }
        }
        LONGLONG currentNumber_s = currentNumber_100ns / 10000000 + 1;
        if (currentNumber_s != displayedNumber)
        {
            system("cls");

            cout << "The guard shoots at you." << endl;
            cout << "'1' To dodge the guards shot" << endl;
            cout << "You have " << currentNumber_s << " seconds to dodge the guard's shot" << endl;
            displayedNumber = currentNumber_s;
        }
    }
    system("pause");
}