zoj 2892 Wavelet Compression

#include <iostream>#include <stdio.h>using namespace std;int main(){int a[300],b[300];int n,i,k,j;while(cin>>n){if(n==0) break;for(i=0;i<n;i++){cin>>a[i];}for(i=1;i<n;i*=2){for(k=0;k<i;k++){b[2*k]=(a[k]+a[i+k])/2;b[2*k+1]=(a[k]-a[i+k])/2;}for(j=0;j<i*2;j++){a[j]=b[j];}}for(i=0;i<n;i++){cout<<a[i];if(i!=n-1)cout<<" ";}cout<<endl;}return 0;}