POJ 2388 基数排序

这题可以直接nth_element过去

比如这样子

//By SiriusRen
#include <cstdio>
#include <algorithm>
using namespace std;
int n,a[100500];
int main(){
    scanf("%d",&n);
    for(int i=1;i<=n;i++)
        scanf("%d",&a[i]);
    nth_element(a+1,a+n/2+1,a+1+n);
    printf("%d\n",a[n/2+1]);
}

我只是想看看我的基数排序模板对不对

//By SiriusRen
#include <cstdio>
#include <cstring>
#include <algorithm>
using namespace std;
#define int unsigned int
int a[10000005],b[10000005],sum[65536],too[65536],n;
signed main(){
    scanf("%d",&n);
    for(int i=1;i<=n;i++)scanf("%u",&a[i]);
    for(int i=1;i<=n;i++)sum[(a[i]<<16)>>16]++;
    for(int i=1;i<65536;i++)too[i]=too[i-1]+sum[i-1];
    for(int i=1;i<=n;i++){
        int x=(a[i]<<16)>>16;
        too[x]++,b[too[x]]=a[i];
    }
    memset(sum,0,sizeof(sum));
    for(int i=1;i<=n;i++)sum[b[i]>>16]++;
    too[0]=0;
    for(int i=1;i<65536;i++)too[i]=too[i-1]+sum[i-1];
    for(int i=1;i<=n;i++){
        int x=b[i]>>16;
        too[x]++,a[too[x]]=b[i];
    }
    printf("%u\n",a[n/2+1]);
}