HDU 1754 I Hate It

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原创最新推荐文章于 2026-09-14 15:36:57 发布 615 阅读 AI 写同款· GEO 优化 ›

【信号与系统实战解析】—— 拉普拉斯变换在电路分析中的关键应用本文深入解析了拉普拉斯变换在电路分析中的关键应用。通过将时域微分方程转换为复频域的代数方程，系统化处理初始条件，并利用零极点图分析电路稳定性与频率响应。文章以RLC串联电路为例，详细演示了s域建模、性质运用及综合分析方法，为工程师提供了分析动态电路的强大工具与清晰视角。阅读详情

Simple segment tree;

The portal:http://acm.hdu.edu.cn/showproblem.php?pid=1754

#include <cstdio>
#include <cstring>
#include <cstdlib>
#include <cmath>
#include <iostream>
#include <algorithm>

using namespace std;

const int MAXN = 200005;

struct Node {
	int value;
	int Left;
	int Right;
}Segment_Tree[MAXN<<2];

int a[MAXN];
int cnt ;

void Build_Tree(int Left,int Right,int Now) {
	Segment_Tree[Now].Left = Left;
	Segment_Tree[Now].Right = Right;
	if(Left == Right) {
		Segment_Tree[Now].value = a[cnt++];
		return ;
	}
	int Mid = (Left + Right) >> 1;
	Build_Tree(Left,Mid,Now<<1);
	Build_Tree(Mid+1,Right,Now<<1|1);
	Segment_Tree[Now].value = max(Segment_Tree[Now<<1].value,Segment_Tree[Now<<1|1].value);
}

void Update_Tree(int Left,int Right,int Now,int position,int change_value) {
	if(Left == Right) {
		Segment_Tree[Now].value = change_value;
		return;
	}
	int Mid = (Left + Right) >> 1;
	if(position > Mid) {
		Update_Tree(Mid+1,Right,Now<<1|1,position,change_value);
	}
	else {
		Update_Tree(Left,Mid,Now<<1,position,change_value);
	}
	Segment_Tree[Now].value = max(Segment_Tree[Now<<1].value,Segment_Tree[Now<<1|1].value);
}

int Query_Tree(int Left,int Right,int Now,int Left_Edge,int Right_Edge) {
	int Query_Ans = 0;
	if(Left >= Left_Edge && Right <= Right_Edge) {
		return Segment_Tree[Now].value;
	}
	int Mid = (Left + Right) >> 1;
	if(Mid >= Left_Edge) {
		Query_Ans = max(Query_Ans,Query_Tree(Left,Mid,Now<<1,Left_Edge,Right_Edge));
	}
	if(Mid < Right_Edge) {
		Query_Ans = max(Query_Ans,Query_Tree(Mid+1,Right,Now<<1|1,Left_Edge,Right_Edge));
	}
	return Query_Ans;
}

void Deal_with() {
	int n,m;
	while(~scanf("%d %d",&n,&m)) {
		for(int i = 1 ; i <= n ; i++) {
			scanf("%d",a+i);
		}
		cnt = 1;
		Build_Tree(1,n,1);
		char tempc;
		int position,value;
		for(int i = 1 ; i <= m ; i++) {
			getchar();
			scanf("%c %d %d",&tempc,&position,&value);
			if(tempc == 'U') {
				Update_Tree(1,n,1,position,value);
			}
			else {
				printf("%d\n",Query_Tree(1,n,1,position,value));
			}
		}
	}
}

int main(void) {
	//freopen("a.in","r",stdin);
	Deal_with();
	return 0;
}