Shuffle array variables in a pre-specified order, without using extra memory of "size of input array"
- by Eternal Learner
Input :
A[4] = {0,4,-1,1000} - Actual Array
P[4] = {1,0,3,2} - Order to be reshuffled
Output:
A[4] = {4,0,1000,-1}
Condition : Don't use an additional array as memory. Can use an extra variable or two.
Problem : I have the below program in C++, but this fails for certain inputs of array P.
#include<iostream>
using namespace std;
void swap(int *a_r,int *r)
{
int temp = *r;
*r = *a_r;
*a_r = temp;
}
int main()
{
int A[4] = {0,4,-1,1000};
int P[4] = {3,0,1,2};
int value = A[0] , dest = P[0];
for(int i=0; i<4;i++)
{
swap(&A[dest],&value);
dest = P[dest];
}
for(int i=0;i<4;i++)
cout<<A[i]<<" ";
}
