Question

Relatively new to C++ and this has been bugging me for a while. I’m trying to write a program that will do different things depending on what random number is generated.

To explain what I’m trying to do simply, lets pretend I’m creating a list of athletes and start by randomly generating their heights within a certain range. Easy to do no problem. Say then I want to generate their weight, based on their height. This is where things get messy. For some reason I can’t figure out, the program is randomly generating the weight based on a different height than the one it returns in the first place. I just don’t get it.

Anyway, here is a piece of (very simplified) sample code that hopefully shows what I’m trying to do. I’m sure I’m missing something obvious but I just can’t seem to figure it out.

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

int random(int min, int max, int base)
{
    int random = (rand() % (max - min) + base);

    return random;
}

int height()
{
    int height = random(1, 24, 60);

    return height;
}

int weight()
{
    int weight = height() * 2.77;

    return weight;
}

void main()
{
    srand ((unsigned int)time(0));

    int n = 1;

    while (n <= 10)
        { 
        cout << height() << " and " << weight() << endl;
        ++n;
        }

    return;
}

Answer 1

It’s quite easy. You call height() in your weight() function. That means you’re getting a new random value for the height. What you have to do is to modify your weight() so that it can pass through a height parameter and calculate the weight based on it (and not on a new random value).

Your new height() function would look as follow:

int weight(int height)
{
    int weight = height * 2.77;

    return weight;
}

In your main():

while (n <= 10)
{
    int h = height();
    int w = weight(h);

    cout << h << " and " << w << endl;
    ++n;
}