CF 56 C

#include<stdio.h>
#include<math.h>
long long int a[1000000],b[100000];
int main()
{
    long long int n,i,k,r,prev,previ,prevn,temp;
    scanf("%lld",&n);
    for(i=1;i<=n/2;i++){
        scanf("%lld",&b[i]);
    }
    prev=b[1];
    previ=0;
    prevn=b[1];
    for(i=1;i<=n/2;i++){
       if(b[i]<=prev){
            a[i]=previ;
            prevn=b[i]-previ;
            a[n-i+1]=prevn;
       }
       else{
            previ=b[i]-prevn;
            prevn=b[i]-previ;
            a[i]=previ;
            a[n-i+1]=prevn;
       }
       prev=b[i];
       previ=a[i];
       prevn=a[n-i+1];
    }
    for(i=1;i<=n;i++){
        printf("%d",a[i]);
        if(i!=n)
            printf(" ");
        else
            printf("\n");
    }
    return 0;
}