Question

following code for partition

#include<iostream>
using namespace std;
#define maxn 10000
int x[maxn];
 void partition(int x[],int p,int r){
   int y=x[p];
   int i=p-1;
   int j=r+1;
   while(i<j){

    do{

     j=j-1;

    } while( x[j]>y);
    do
    {
     i=i+1;


    } while(x[j]<y);

    if (i<j){  int s=x[i];x[i]=x[j];x[j]=s;   }

             if (i>=j) break;

   }



  }

int main(){


          int n=12;
               for (int i=1;i<=n;i++)  cin  >>x[i];
               partition(x,1,n);
                for (int i=1;i<=n;i++)  cout<<x[i]<<" ";





 return 0;
}

does not work,it means that when i enter some numbers,and press enter it does not worite anything,neither partitioned array of course,please help me

Answer 1

I don`t really what are you trying but may be second while comparison:

while(x[j]<y)

must be changed by

while(x[i]<y)