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Check if a given array is pair wise sorted or not

Here is the program to check if a given array is pair wise sorted or not using C:

C program to check if a given array is pair wise sorted or not

#include <stdbool.h>
#include <stdio.h>

bool checkPairwiseSorted(int arr[], int size) {
  for (int i = 0; i < size - 1; i += 2) {
    if (arr[i] > arr[i + 1]) {
      return false;
    }
  }
  return true;
}

int main() {
  int arr1[] = {10, 20, 30, 40, 50, 60};
  int arr_size1 = sizeof(arr1) / sizeof(arr1[0]);

  int arr2[] = {20, 10, 30, 50, 60, 40};
  int arr_size2 = sizeof(arr2) / sizeof(arr2[0]);

  if (checkPairwiseSorted(arr1, arr_size1)) {
    printf("Array (arr1) is pair-wise sorted.\n");
  } else {
    printf("Array (arr1) is not pair-wise sorted.\n");
  }

  if (checkPairwiseSorted(arr2, arr_size2)) {
    printf("Array (arr2) is pair-wise sorted.\n");
  } else {
    printf("Array (arr2) is not pair-wise sorted.\n");
  }

  return 0;
}

Output

Array (arr1) is pair-wise sorted.
Array (arr2) is not pair-wise sorted.