Comparing Two Arrays in C: By Contents and By Address

This C program compares two distinct arrays and if the arrays are same then content results in FALSE. The behavior of comparison is explained when we note that the comparison is a comparison of addresses, not contents.

Comparing Arrays by Addresses

#include < stdio.h >

  int main(void) {
    int a[2] = {1, 2}; 
    int b[2] = {2, 3};
    int i;

    for (i = 0; i < 2; i++) {
      a[i] = b[i];
    }

    // The comparison of two distinct arrays with the same content
    // results in FALSE. So below we print "They are not equal"
    if (a == b) {
      printf("They are equal\n");
    } else {
      printf("They are not equal\n");
    }

    // The following comparison results in TRUE. 
    if (a == a) {
      printf("Of course a is equal to a\n");
    } else {
      printf("No, a is not equal to a\n");
    }

        //  Print the elements of array a
    for (i = 0; i < 2; i++) {
        printf("a[%d] = %d\n", i, a[i]);
    }

    //  Print the elements of array b
    for (i = 0; i < 2; i++) {
        printf("a[%d] = %d\n", i, b[i]);
    }
  }

#include < stdio.h >

int main(void) {

int a[2] = {1, 2};

int b[2] = {2, 3};

int i;

for (i = 0; i < 2; i++) {

a[i] = b[i];

}

// The comparison of two distinct arrays with the same content

// results in FALSE. So below we print "They are not equal"

if (a == b) {

printf("They are equal\n");

} else {

printf("They are not equal\n");

}

// The following comparison results in TRUE.

if (a == a) {

printf("Of course a is equal to a\n");

} else {

printf("No, a is not equal to a\n");

}

// Print the elements of array a

for (i = 0; i < 2; i++) {

printf("a[%d] = %d\n", i, a[i]);

}

// Print the elements of array b

for (i = 0; i < 2; i++) {

printf("a[%d] = %d\n", i, b[i]);

}

Comparing Arrays by Addresses

In this updated code, we added a loop to compare each element of arrays a and b. If any pair of corresponding elements is not equal, the equal variable is set to 0, indicating that the arrays are not equal. The result is then printed based on the value of the equal variable.

#include <stdio.h>

int main(void) {
    int a[2] = {1, 2};
    int b[2] = {2, 3};
    int i;

    // Copy elements from array b to array a 
    for (i = 0; i < 2; i++) {
        a[i] = b[i];
    }

    // Compare the contents of arrays a and b 
    int equal = 1; // Assume arrays are equal

    for (i = 0; i < 2; i++) {
        if (a[i] != b[i]) {
            equal = 0; // Arrays are not equal
            break;
        }
    }

    // Print the result based on the equality check 
    if (equal) {
        printf("They are equal\n");
    } else {
        printf("They are not equal\n");
    }

    //  Print the elements of array a
    for (i = 0; i < 2; i++) {
        printf("a[%d] = %d\n", i, a[i]);
    }

    //  Print the elements of array b
    for (i = 0; i < 2; i++) {
        printf("a[%d] = %d\n", i, b[i]);
    }

    return 0;
}

#include <stdio.h>

int main(void) {

int a[2] = {1, 2};

int b[2] = {2, 3};

int i;

// Copy elements from array b to array a

for (i = 0; i < 2; i++) {

a[i] = b[i];

}

// Compare the contents of arrays a and b

int equal = 1; // Assume arrays are equal

for (i = 0; i < 2; i++) {

if (a[i] != b[i]) {

equal = 0; // Arrays are not equal

break;

}

// Print the result based on the equality check

if (equal) {

printf("They are equal\n");

} else {

printf("They are not equal\n");

}

// Print the elements of array a

for (i = 0; i < 2; i++) {

printf("a[%d] = %d\n", i, a[i]);

}

// Print the elements of array b

for (i = 0; i < 2; i++) {

printf("a[%d] = %d\n", i, b[i]);

}

return 0;

}

Comparing Two Arrays in C: By Contents and By Address

Comparing Arrays by Addresses

Comparing Arrays by Addresses

About The Author

M. Saqib

Comparing Two Arrays in C: By Contents and By Address

Comparing Arrays by Addresses

Comparing Arrays by Addresses

About The Author

M. Saqib

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