# ABSOLUTE-PERMUTATION hackerrank Solution - Correct, Optimal and Working

``````/*
*  Author: Arpit Bhayani
*  https://arpitbhayani.me
*/
#include <cmath>
#include <cstdio>
#include <cstdlib>
#include <climits>
#include <deque>
#include <iostream>
#include <list>
#include <limits>
#include <map>
#include <queue>
#include <set>
#include <stack>
#include <vector>

#define ll long long

#define MIN(a, b) a < b ? a : b
#define MAX(a, b) a > b ? a : b

using namespace std;

int i = 0;
char ch;
while((ch = getchar()) != '\n') {
str[i++] = ch;
}
str[i] = '\0';
return i;
}

int arr[100010];

void print_array(int n) {
for(int i = 1; i <= n; i++) {
printf("%d ", arr[i]);
}
printf("\n");
}

int process(int n, int k) {
for(int i = 1; i <= n; i++) {
arr[i] = i;
}

if(k == 0) {
return 0;
}

int index = 1;
while(1) {
for(int j = 0; j < k; j++) {
if(index + j + k > n) {
return -1;
}
int t = arr[index + j];
arr[index + j] = arr[index + j + k];
arr[index + j + k] = t;
}
index += (2*k);
if(index == n + 1) {
return 0;
}
if(index > n + 1) {
return -1;
}
}
}

int main(int argc, char *argv[]) {
int t;
scanf("%d", &t);

while(t--) {
int n, k;
scanf("%d%d", &n, &k);
int ans = process(n, k);

if(ans == -1) {
printf("-1\n");
}
else {
print_array(n);
}
}

return 0;
}
``````