Thread: problem in returning array to main.

Hi all,

I am returning to programming after a long time.

Code:

#include <stdio.h>


void test_armstrong(int number, int *array)
{
    int a[4], sum,i, j, temp;
        
    temp = number;
    
    a[3]   =  number/1000;
    number =  number - (a[3]*1000);
    a[2]   =  number/100;
    number =  number - (a[2]*100);
    a[1]   =  number/10;        
    number =  number - (a[1]*10);
    a[0]   =  number;
    
    sum = 0;
       
    for (i = 0; i < 4 ; i++)
    {
        a[i] = a[i]*a[i]*a[i]*a[i];
        sum = sum + a[i];
    }
    
        if (sum == temp)
           {                  
                  *array = temp;
                  printf("Armstrong number %d\n", *array);
                  array++;
            }      
}


int main()
{
    int i, j, number, start, end;
    int array[] = {NULL};
    
    start = 1000;
    end = 9999; 
    
    for( i = start; i <= end; i++)
    {         
                number =  i;       
          test_armstrong(number, array);
    }        
    
    printf("\n\n%d\n", *array);
}

.


I want the print of the array in the function and the print of array to be the same but I am only getting the last number of array when printing the array in the main function. Please help me. Thankyou.

You can't return arrays.
Nor can you print a whole array using printf.
Nor is an array inherently aware of it's capacity.

Code:

#include <stdio.h>

void test_armstrong(int number, int *array, int *nResults)
{
    int a[4], sum,i, j, temp;
        
    temp = number;
    
    a[3]   =  number/1000;
    number =  number - (a[3]*1000);
    a[2]   =  number/100;
    number =  number - (a[2]*100);
    a[1]   =  number/10;        
    number =  number - (a[1]*10);
    a[0]   =  number;
    
    sum = 0;
       
    for (i = 0; i < 4 ; i++)
    {
        a[i] = a[i]*a[i]*a[i]*a[i];
        sum = sum + a[i];
    }
    
        if (sum == temp)
           {                  
                  array[*nResults] = temp;
                  printf("Armstrong number %d\n", array[*nResults]);
                  (array[*nResults])++;
            }      
}


int main()
{
    int i, j, number, start, end;
    int array[20] = {0};  // how many?
    int nResults = 0;
    
    start = 1000;
    end = 9999; 
    
    for( i = start; i <= end; i++)
    {         
                number =  i;       
          test_armstrong(number, array, &nResults);
    }        
    
    printf("\n\n%d\n", nResults);
    // a for loop is left as an exercise to the reader.

    return 0;  // so you don't see something silly like return 7
}