Program to copy the greater than and lesser than 30 integers from a one-dimensional array to two three-dimensional arrays in c

Question

I'm trying to make a program allowing a user to input positive integers into a one-dimensional array size 12 and trap inputs less than 1. The program then copies integers with a value less than 30 into a second three-dimensional array. And it also copies the integers greater than or equal to 30 into a third three-dimensional array.

It will display the three arrays together in a tabular form. The program will use three arrays, 1 single array, and 2 three-dimensional arrays.

This is what I did:

#include <stdio.h>

#define N 12


int main() {

    int a[N], b[2][2][3], c[2][2][3];
    int i, j, k, l;

        for(i = 0; i < N; i++){
            printf("Input %d: ", i);
            scanf("%d", &a[i]);

            if(a[i] < 30){
                for(j = 0; j < 2; j++){
                    for(k = 0; k < 2; k++){
                        for(l = 0; l < 3; l++){
                            b[j][k][l] = a[i];
                        }
                    }
                }
            }

            if(a[i] >= 30){
                for(j = 0; j < 2; j++){
                    for(k = 0; k < 2; k++){
                        for(l = 0; l < 3; l++){
                            c[j][k][l] = a[i];
                        }
                    }
                }
            }

            while(a[i] < 1){
                if (a[i] < 5){
                    printf("\nInvalid Input\nEnter 1 or greater than 1 only\n\n");
                    printf("Input %d: ", i);
                    scanf("%d", &a[i]);

                    if(a[i] < 30){
                        for(j = 0; j < 2; j++){
                            for(k = 0; k < 2; k++){
                                for(l = 0; l < 3; l++){
                                    b[j][k][l] = a[i];
                                }
                            }
                        }
                    }

                    if(a[i] >= 30){
                        for(j = 0; j < 2; j++){
                            for(k = 0; k < 2; k++){
                                for(l = 0; l < 3; l++){
                                    c[j][k][l] = a[i];
                                }
                            }
                        }
                    }
                }
            }

        }

        printf("\nArray 1: \n");

        for(i = 0; i < N; i++)
            printf("a[%d] = %d \n", i, a[i]);

        printf("\n\nArray with less than 30: \n");

        for(j = 0; j < 2; j++){
                    for(k = 0; k < 2; k++){
                        for(l = 0; l < 3; l++){
                            printf("b[%d][%d][%d] = %d \n", j, k, l, b[j][k][l]); 
                        }
                    }
                }

        printf("\n\nArray with greater than or equal to 30: \n");

        for(j = 0; j < 2; j++){
                    for(k = 0; k < 2; k++){
                        for(l = 0; l < 3; l++){
                            printf("c[%d][%d][%d] = %d \n", j, k, l, c[j][k][l]); 
                        }
                    }
                }
}

However when I try to run the program it displays the wrong values. Could someone please enlighten me what's wrong with my code? Thank you.

Edit: I have changed the indexing to start with 0 not 1.

When I try to input this:

Input 0: 1
Input 1: 2
Input 2: 3
Input 3: 4
Input 4: 5
Input 5: 6
Input 6: 31
Input 7: 32
Input 8: 33
Input 9: 34
Input 10: 35
Input 11: 36

It shows the result I want in array 1:

Array 1:
a[0] = 1
a[1] = 2
a[2] = 3
a[3] = 4
a[4] = 5
a[5] = 6
a[6] = 31
a[7] = 32
a[8] = 33
a[9] = 34
a[10] = 35
a[11] = 36

However, in both the three-dimensional arrays, it only displays the last integer that I have inputted that fits the condition:

Array with less than 30:
b[0][0][0] = 6
b[0][0][1] = 6
b[0][0][2] = 6
b[0][1][0] = 6
b[0][1][1] = 6
b[0][1][2] = 6
b[1][0][0] = 6
b[1][0][1] = 6
b[1][0][2] = 6
b[1][1][0] = 6
b[1][1][1] = 6
b[1][1][2] = 6


Array with greater than or equal to 30:
c[0][0][0] = 36
c[0][0][1] = 36
c[0][0][2] = 36
c[0][1][0] = 36
c[0][1][1] = 36
c[0][1][2] = 36
c[1][0][0] = 36
c[1][0][1] = 36
c[1][0][2] = 36
c[1][1][0] = 36
c[1][1][1] = 36
c[1][1][2] = 36

What I'm trying to get is that in the three-dimensional arrays "Array with less than 30:" displays ALL less than 30

And also in "Array with greater than or equal to 30:" displays ALL greater than or equal to 30.

Like this:

Array with less than 30:
b[0][0][0] = 1
b[0][0][1] = 2
b[0][0][2] = 3
b[0][1][0] = 4
b[0][1][1] = 5
b[0][1][2] = 6
b[1][0][0] = 0
b[1][0][1] = 0
b[1][0][2] = 0
b[1][1][0] = 0
b[1][1][1] = 0
b[1][1][2] = 0


Array with greater than or equal to 30:
c[0][0][0] = 31
c[0][0][1] = 32
c[0][0][2] = 33
c[0][1][0] = 34
c[0][1][1] = 35
c[0][1][2] = 36
c[1][0][0] = 0
c[1][0][1] = 0
c[1][0][2] = 0
c[1][1][0] = 0
c[1][1][1] = 0
c[1][1][2] = 0

Would it be possible to do this? Or are there any alternatives that are similar?

Answer 1

The following might show how to use less code to achieve your objective. Please note that the printing of b[] and c[] could be done in a function called twice (instead of duplicated code.)

#include <stdio.h>

#define N 12

int main( void ) {
    int a[N] = { 0 } // initialise arrays on the stack
    int b[2][2][3] = { 0 };
    int c[2][2][3] = { 0 };
    int i, j, k, l;

    for( i = 0; i < N; i++ ) {
        // localise validation of user input
        do {
            printf("Input %d: ", i);
#if 0
            if( scanf( "%d", &a[i] ) != 1 || a[i] < 1 )
                puts( "Bad input. Repeat..." );
#else // correction to clear the input buffer if user enters "foobar"
            if( scanf( "%d", &a[i] ) != 1 || a[i] < 1 ) {
                scanf( "%*[^\n]" );
                puts( "Bad input. Repeat..." );
            }
#endif
        } while( a[i] < 1 );

        int done = 0; // a flag (to break out of nested loops.
        for(j = 0; j < 2 && !done; j++)
            for(k = 0; k < 2 && !done; k++)
                for(l = 0; l < 3 && !done; l++)
                    if( a[i] < 30 ) {
                        if( b[j][k][l] == 0 ) { // only replace 0's
                            b[j][k][l] = a[i];
                            done = 1;
                        }
                    } else {
                        if( c[j][k][l] == 0 ) {
                            c[j][k][l] = a[i];
                            done = 1;
                        }
                    }
    }
    
    /* then do the printing stuff */
}

Don't use copy/paste to write code. And, don't write more than a few lines of code before stopping to compile and test what you've written/changed. "Incremental development".

---

EDIT:
Having pressured the OP to write less code that does the job, it seems appropriate to improve on the offering above. This still uses the 3D array for storage.

    int *store = NULL;
    for(j = 0; j < 2 && !store; j++)
        for(k = 0; k < 2 && !store; k++)
            for(l = 0; l < 3 && !store; l++)
                if( a[i] < 30 ) {
                    if( b[j][k][l] == 0 )
                        store = &b[j][k][l];
                } else {
                    if( c[j][k][l] == 0 ) {
                        store = &c[j][k][l];
                }
    *store = a[i];