北航复试机试题

题目1167：数组排序

数据量小得可怜，完全可以最用朴素的方法。

本代码：快速排序，二分查找输出。

#include <stdio.h>
typedef struct node
{
    int val,idx;
}node;
node c[10000];
int d[10000];
void swap(node *a,node *b)
{
    int t;
    t = a->val;
    a->val = b->val;
    b->val = t;
}
void quick(int left,int right)
{
    int l,r;
    l = left +1;
    r = right;
    if(left >=right)return;
    int key = c[left].val;
    while(1)
    {
        while(c[r].val> key)r--;
        while(c[l].val<key&&l<r)l++;
        if(l>=r)break;
        swap(&c[l],&c[r]);
        if(c[l].val == c[left].val)r--;
        else l++;
    }
    swap(&c[left],&c[r]);
    if(left<l-1)quick(left, l-1);
    if(r+1<right)quick(r+1, right);
}
int binary0(int l,int r,int key)
{
    int mid = (l+r)/2;
    if(c[mid].val == key)return c[mid].idx;
    if(c[mid].val>key)return binary0(l, mid-1, key);
    else return binary0(mid+1, r, key);
    
}
int main(int argc, const char * argv[])
{
    int n,i;
    while(scanf("%d",&n)!=EOF)
    {
        for(i=0;i<n;i++)
        {
            scanf("%d",&c[i].val);
            d[i] = c[i].val;
            //c[i].idx = i;
        }
        quick(0, n-1);
        c[0].idx = 1;
        for (i=1; i<n; i++) {
            if(c[i].val!=c[i-1].val){c[i].idx = c[i-1].idx+1;}
            else c[i].idx = c[i-1].idx;
        }
        for (i=0; i<n; i++) {
            if(i!=0)printf(" ");
            printf("%d",binary0(0, n-1, d[i]));
        }
        printf("
");
       
    }
}