前言

有回来做$B$B组了，话说第3道题就是$A$A组第一道。

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成绩

$Rank$Rank是有算别人的
今天$XJQ$XJQ不在

$Rank$Rank	$Person$Person	$Score$Score	$A$A	$B$B	$C$C
$1$1	$2017wyc$2017wyc	$270$270	$100$100	$100$100	$70$70
$10$10	$2017hjq$2017hjq	$130$130	$100$100	$30$30	$0$0
$10$10	$2017zyc$2017zyc	$130$130	$100$100	$30$30	$0$0
$16$16	$2017xxy$2017xxy	$120$120	$100$100	$20$20	$0$0
$39$39	$2017lw$2017lw	$30$30	$0$0	$30$30	$0$0
$46$46	$2017hzb$2017hzb	$20$20	$0$0	$20$20	$0$0
$46$46	$2017lrz$2017lrz	$20$20	$0$0	$20$20	$0$0

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正题

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$T1:jzoj4229-$T1:jzoj4229−学习神技【逆元$,$,费马小定理】

博客链接:
https://blog.csdn.net/Mr_wuyongcong/article/details/86561722

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$T2:jzoj4230-$T2:jzoj4230−淬炼神体【$0/1$0/1分数规划】

博客链接:
https://blog.csdn.net/Mr_wuyongcong/article/details/86561780

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$T3:jzoj4231-$T3:jzoj4231−寻找神格【线段树$,$,数学】

神TM这道题有SPJ，让我输出3位小数，输出到10位就过了
誓死力争，还我AK!
博客链接:
https://blog.csdn.net/Mr_wuyongcong/article/details/86561899

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$some\ of\ code$some of code

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T2暴力

#include<cstdio>
#include<algorithm>
using namespace std;
int n,k,a[16],b[16];
double ans;
int v[16];
double check()
{
	int sum_a=0,sum_b=0;
	for(int i=1;i<=n;i++)
	  if(v[i]) 
	    sum_a+=a[i],sum_b+=b[i];
	return (double)sum_a/sum_b;
}
void dfs(int dep,int c){
	if(c==k){
		ans=max(check(),ans);
		if(ans>=2000)
		  ans++,ans--;
		check();
		return;
	}
	if(dep>n) return;
	v[dep]=1;
	dfs(dep+1,c+1);
	v[dep]=0;
	dfs(dep+1,c);
}
int main()
{
	freopen("data.in","r",stdin);
	freopen("data.anss","w",stdout);
	scanf("%d%d",&n,&k);
	for(int i=1;i<=n;i++)
	  scanf("%d",&a[i]);
	for(int i=1;i<=n;i++)
	  scanf("%d",&b[i]);
	dfs(1,0);
	printf("%0.3lf",ans);
}

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T2随机数据

#include<cstdlib>
#include<algorithm>
#include<cstdio>
#include<ctime>
#define random(x) rand()%x+1
using namespace std;
int main()
{
	freopen("data.in","w",stdout);
	srand(time(0));
	printf("15 %d\n",random(15));
	for(int i=1;i<=15;i++)
	  printf("%d ",random(1000));
	printf("\n");
	for(int i=1;i<=15;i++)
	  printf("%d ",random(1000));
}

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T3暴力

#include<cstdio>
#define ll long long
using namespace std;
ll n,m,p[5010];
int main()
{
	//freopen("data.in","r",stdin);
	//freopen("data.ans","w",stdout);
	scanf("%lld%lld",&n,&m);
	for(ll i=1;i<=n;i++)
	  scanf("%lld",&p[i]);
	for(ll i=1;i<=m;i++)
	{
		ll t,a,b;
		scanf("%lld%lld%lld",&t,&a,&b);
		if(t==0) p[a]+=b;
		else if(t==1){
			ll z;scanf("%lld",&z);
			for(ll i=a;i<=b;i++)
			  p[i]+=z;
		}
		else if(t==2){
			ll ans=0;
			for(ll i=a;i<=b;i++)
			  ans+=p[i];
			printf("%lld\n",ans);
		}
		else{
			double n=(b-a+1),ans=0,sum=0;
			for(ll i=a;i<=b;i++)
			  sum+=p[i];
			sum/=n;
			for(ll i=a;i<=b;i++)
			  ans+=(double(p[i])-sum)*(double(p[i])-sum);
			ans/=n;
			printf("%0.3lf\n",ans);
		}
	}
}

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T3随机数据

#include<cstdio>
#include<ctime>
#include<cstdlib>
#include<algorithm>
using namespace std;
int n,m,k;
int main()
{
	srand(time(0));
	//freopen("data.in","w",stdout);
	n=5;m=5;k=10;
	printf("%d %d\n",n,m);
	for(int i=1;i<=n;i++)
	  printf("%d ",rand()%k*2-k);
	printf("\n");
	for(int i=1;i<=n;i++)
	{
		int t=rand()%4,a=rand()%n+1,b=rand()%n+1;
		printf("%d ",t);
		if(a>b) swap(a,b);
		if(t==0)
			printf("%d %d\n",a,rand()%k*2-k);
		else if(t==1) 
			printf("%d %d %d\n",a,b,rand()%k*2-k);
		else if(t==2)
			printf("%d %d\n",a,b);
		else printf("%d %d\n",a,b);
	}
}

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尾声

誓死力争，还我AK!