Thread: Printing asterisks using user input

Hello. I'm in the process of writing a program that does the following:

1. Ask user for input of five numbers, each between 1 and 30
2. Check if those numbers are between 1 and 30 (if not, tell them)
3. Use functions for the while loop and checking if the number is between 1 and 30 (two seperate functions)
4. Take that number, print number of asterisks (each in a new line)

I've written the program for the most part, but can't figure out how to use functions when needed. Can someone help me out? Thanks.

Code:

#include <stdio.h>
int main()
{
	int num=0,num1=0,num2=0,num3=0,num4=0;
	printf("Please enter five numbers that are between 1 and 30: ");
	scanf("%d",&num);
	scanf("%d",&num1);
	scanf("%d",&num2);
	scanf("%d",&num3);
	scanf("%d",&num4);
	if(num > 30)
		{
			printf("One or more of the numbers you entered was greater than 30. Try again: ");
			scanf("%d",&num);	
		}
	if(num < 1 || num==1)
		{
			printf("One of the numbers you entered was less than 1 or 1. Try again: ");
			scanf("%d",&num);	
		}
	if(num1 > 30)
		{
			printf("The number you entered was greater than 30. Try again: ");
			scanf("%d",&num1);	
		}
	if(num1 < 1 || num1==1)
		{
			printf("One of the numbers you entered was less than 1 or 1. Try again: ");
			scanf("%d",&num1);	
		}
	if(num2 > 30)
		{
			printf("The number you entered was greater than 30. Try again: ");
			scanf("%d",&num2);	
		}
	if(num2 < 1 || num2==1)
		{
			printf("One of the numbers you entered was less than 1 or 1. Try again: ");
			scanf("%d",&num2);	
		}
	if(num3 > 30)
		{
			printf("The number you entered was greater than 30. Try again: ");
			scanf("%d",&num3);	
		}
	if(num3 < 1 || num3==1)
		{
			printf("One of the numbers you entered was less than 1 or 1. Try again: ");
			scanf("%d",&num3);	
		}
	if(num4 > 30)
		{
			printf("The number you entered was greater than 30. Try again: ");
			scanf("%d",&num4);	
		}
	if(num4 < 1 || num4==1)
		{
			printf("One of the numbers you entered was less than 1 or 1. Try again: ");
			scanf("%d",&num4);	
		}

	while(num < 30 || num > 1)
		{
			for(;num>0;num--)
				{
					printf("*");
				}
			printf("\n");
		}
	while(num1 < 30 || num1 > 1)
		{
			for(;num1>0;num1--)
				{
					printf("*");
				}
			printf("\n");
		}
	while(num2 < 30 || num2 > 1)
		{
			for(;num2>0;num2--)
				{
					printf("*");
				}
			printf("\n");
		}
	while(num3 < 30 || num3 > 1)
		{
			for(;num3>0;num3--)
				{
					printf("*");
				}
			printf("\n");
		}
	while(num4 < 30 || num4 > 1)
		{
			for(;num4>0;num4--)
				{
					printf("*");
				}
			printf("\n");
		}
}

Originally Posted by quzah

You could replace all those if checks with a function that returns only when a number between 1 and 30 was entered, and then use it something like this:

Code:

num1 = get1to30();

Then make a function called 'get1to30' that has the user keep retrying until a valid number is entered. That's just a simple way to do it. You could get a bit more complex, and pass 'low' and 'high' to it, and make it work for any valid range:

Code:

num1 = getrangednumber( 1, 30 );

Basically you make functions be small tools to handle a job that you may need to do multiple times. It saves you from writing the same big block of code over and over.


Quzah.

I can write a function for one user input relatively easily - it's just when it gets to five. I'm not sure where to even start with it.

Ok... something to think about...

1) can your num variables be made into an array?

2) Can you process arrays in loops?