How to check if Two Arrays have Same Elements (Regardless of Order) in C - Step by Step Examples

How to check if Two Arrays have Same Elements (Regardless of Order) in C ?

Answer

To check if two arrays have the same elements regardless of order in C, you can sort both arrays and then compare them element by element.

✐ Examples

1 Arrays with Same Elements (Order Ignored)

In this example,

We create two arrays named arr1 and arr2 with the same elements but in different order.
We sort both arrays using the qsort function from the stdlib.h library.
We then define a function arraysEqual that checks if the sorted arrays are equal.
Finally, we call arraysEqual to compare the arrays and print the result to the console.

C Program

#include <stdio.h>
#include <stdlib.h>
#include <string.h>

int compare(const void *a, const void *b) {
    return (*(int*)a - *(int*)b);
}

int arraysEqual(int arr1[], int arr2[], int size) {
    qsort(arr1, size, sizeof(int), compare);
    qsort(arr2, size, sizeof(int), compare);

    for (int i = 0; i < size; i++) {
        if (arr1[i] != arr2[i]) {
            return 0;
        }
    }
    return 1;
}

int main() {
    int arr1[] = {1, 2, 3};
    int arr2[] = {3, 1, 2};
    int size = sizeof(arr1) / sizeof(arr1[0]);

    int isEqual = arraysEqual(arr1, arr2, size);
    printf("%s\n", isEqual ? "true" : "false");
    return 0;
}

Output

true

2 Arrays with Different Elements (Order Ignored)

In this example,

We create two arrays named arr3 and arr4 with different elements.
We sort both arrays using the qsort function from the stdlib.h library.
We then define a function arraysEqual that checks if the sorted arrays are equal.
Finally, we call arraysEqual to compare the arrays and print the result to the console.

C Program

#include <stdio.h>
#include <stdlib.h>
#include <string.h>

int compare(const void *a, const void *b) {
    return (*(int*)a - *(int*)b);
}

int arraysEqual(int arr1[], int arr2[], int size) {
    qsort(arr1, size, sizeof(int), compare);
    qsort(arr2, size, sizeof(int), compare);

    for (int i = 0; i < size; i++) {
        if (arr1[i] != arr2[i]) {
            return 0;
        }
    }
    return 1;
}

int main() {
    int arr3[] = {1, 2, 3};
    int arr4[] = {4, 5, 6};
    int size = sizeof(arr3) / sizeof(arr3[0]);

    int isEqual = arraysEqual(arr3, arr4, size);
    printf("%s\n", isEqual ? "true" : "false");
    return 0;
}

Output

false

Summary

In this tutorial, we learned How to check if Two Arrays have Same Elements (Regardless of Order) in C language with well detailed examples.

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How to check if Two Arrays have Same Elements (Regardless of Order) in C - Step by Step Examples

How to check if Two Arrays have Same Elements (Regardless of Order) in C ?

Answer

✐ Examples

1 Arrays with Same Elements (Order Ignored)

C Program

Output

2 Arrays with Different Elements (Order Ignored)

C Program

Output

Summary

More C Arrays Tutorials