Re-enter a user input

This is a portion of my code for a game. If the user enters a number > 9 it does cout the response however it just keeps going. It does not stop the program and allow the user to re enter the number. My question is how do I allow the user to re enter the number whenever they enter the wrong thing.

 
{
 if ( number <= 9) // 
   {
    cout << "That number works. Next player" << endl;
    return 1; 
   } 

 else  if (num1 > 9);
   {
 cout << "That number is invalid. Please make sure you enter a number between 1 and 9" << endl;
return 0; 
   }
}

Also is there a way for me to stop the user from entering the same number twice without using a vector. For example if the user enters 9 and then then they enter 9 again it will cout something like " you entered that number already" and then allow them to enter a different number.
Hope I was clear enough thank you in advance.

McNo (45)

Try using a while loop

while (number > 9){
cout << "That number is invalid. Please make sure you enter a number between 1 and 9" << endl;
}
cout << "That number works. Next player" << endl;
return 1;

GhostCas (19)

player 1 pick your number
10
That number is invalid. Please make sure you enter a number between 1 and 9
0 | 1 | 10
------------
9| 2 | 8
------------
6 | 3| 7
No winner yet! Next player
Player 2 pick your spot! (x,y)

Used the while loop @McNo but it still keeps playing after it states the number is invalid

McNo (45)

Could you post a bit more of your code?

GhostCas (19)


#include <iostream>
#include "playgame.h"
#include "validate.h"
using namespace std; 

bool play(int number, int vortex[3][3]) 
{
int x, y;

  for (int i=0; i<3; i++) 
    {
      for (int j=0; j<3; j++) 
      {

cout << "Player 1 choose your position(x,y)" << endl;
cin >> x >> y;

cout << "player 1 pick your number" << endl; 
cin >> number; 

vortex [x][y]  = number;
validate (number);
display (vortex);
whowins(vortex);
	
cout << "Player 2 pick your coordinates! (x,y)" << endl;
cin >> x >> y; // Postion for player 2

cout << "Player 2 pick your number" << endl;
cin >> number; // number that is being played by player 2
 vortex[x][y] = num1;
validate (num1);
display (matrix);

if (checkforwin (vortex) == false);{
return 0; }
      }
    }
}

       
bool validate (int number) // Validate function
{
 while (num1 > 9){
cout << "That number is invalid. Please make sure you enter a number between 1 and 9" << endl;
 return 0;
}
cout << "That number works. Next player" << endl;
return 1; 
}

McNo (45)

Thanks. Try instead of validate (number); using

1
2
3

while (!validate(number)) {
cin >> number;
}

And switch your bool validate (int number) function to the way you had it before:

 
{
 if ( number <= 9) // 
   {
    cout << "That number works. Next player" << endl;
    return 1; 
   } 

 else  if (num1 > 9);
   {
 cout << "That number is invalid. Please make sure you enter a number between 1 and 9" << endl;
return 0; 
   }
}

This way the user must enter a valid input before your program continues.

Last edited on

GhostCas (19)

player 1 pick your number
Good job! That number works. Next player
0 | 0 | 0
------------
0 | 0 | 0
------------
0 | 0 | 0
No winner , keep playing!

Tried that but it won't let me input the number now

GhostCas (19)

Bump still having this problem

megatron 0 (471)

// I used doubles so it works for both int and double values
bool Validate(double value, double low, double high)
{
    if(value < low || value > high) return 0;
    return 1;
}

void GetInput(const std::string& prompt, int& value)
{
    while(std::cout << prompt << ": ", std::cin >> value)
    {
        if(Validate(value,1,9)) return;
    }
    std::cout << "Error: Wrong data type or failure on stdin!";
}

int main()
{
    int i;
    GetInput("Enter a number between 1 and 9",i);
    std::cout << "You entered << i << "\n";
}

Hope this helps.

GhostCas (19)

The code that i showed was only for one of my .cpp files I thought I could make it work by only editing my bool validate function. I'll try to implement what you said though.

megatron 0 (471)

Try reorganising your code, it seems very bloated to me and you make simple functions bulky.

Also could you explain what that for-loop is for in bool play()? I don't see i or j used anywhere?

Also you may want to check the input on cin when asking the user for coordinates. It's screaming out of bounds exception when you write vortex[x][y].

If you need any more help just ask.

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Re-enter a user input