用于计算平均数，方差，众数，中位数，极差

#include<algorithm>
#include<cstdio>
#include<iostream>
#include<cmath>
using namespace std;
int main(){
	double fc=0,pj=0,jc=0,zw=0,zs=0;
	int n,a[1000],sum=0,cx[1005],mm=0,nn=1000,xsc[1005]={0},max=0;
	scanf("%d",&n);
	for(int i=1;i<=n;i++){
		scanf("%d",&a[i]);
		if(a[i]>=mm) mm=a[i];
		if(a[i]<=nn) nn=a[i];
		sum+=a[i];
		cx[a[i]]++;
		if(cx[a[i]]>max){
			max=cx[a[i]];
		}
	}
	sort(a+1,a+1+n);
	jc=mm-nn;
	pj=sum*1.0/n;
	for(int i=1;i<=n;i++){
		fc=fc+(a[i]-pj)*(a[i]-pj);
	}
	if(n%2==0) zw=(a[n/2]+a[n/2+1])/2;
	else zw=a[n/2+1];
	printf("平均数为:%.3lf\n",pj);
	printf("中位数为:%.3lf\n",zw);
	printf("方差为:%.3lf\n",fc);
	printf("极差为:%.3lf\n",jc);
	printf("众数为:");
	for(int i=1;i<=n;i++){
		if(cx[a[i]]==max && xsc[a[i]]==0){
			printf("%d ",a[i]);
			xsc[a[i]]=1;
		}
	}
	return 0;
}