HDU 1754 I Hate It

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这题算是最基本的线段树的题目
如果刚学习线段树的还是建议自己不要看代码独立的把代码敲出来。
不过这道题还是给我一点教训尽量别用cin cout 这个会卡一些时间
题目链接：http://acm.hdu.edu.cn/showproblem.php?pid=1754

#include<map>#include<set>#include<stack>#include<cmath>#include<queue>#include<bitset>#include<math.h>#include<vector>#include<string>#include<stdio.h>#include<cstring>#include<iostream>#include<algorithm>#define lson l, mid, rt<<1#define rson mid + 1, r, rt<<1|1//#pragma comment(linker, "/STACK:102400000,102400000")using namespace std;typedef double db;typedef long long ll;typedef unsigned int uint;typedef unsigned long long ull;const db eps = 1e-5;const int N = 1e6 + 10;const int M = 1e5 + 10;const ll MOD = 1000000007;const int mod = 1000000007;const int MAX = 1000000010;const double pi = acos(-1.0);const int MAXN=200000;int T[MAXN << 2];void PushUp(int rt){    T[rt] = max(T[rt << 1] ,T[rt << 1 |1]);}void Build(int l,int r,int rt){    if (l == r)    {        scanf("%d",&T[rt]);        return;    }    int mid = (r + l) >>1;    Build(lson);    Build(rson);    PushUp(rt);}void Update(int P, int C, int l, int r, int rt){    if (l == r)    {        T[rt] = C;        return;    }    int mid = (r + l)>>1;    if(P<=mid) Update(P, C, lson);    else Update(P, C, rson);    PushUp(rt);}int query(int L, int R, int l, int r, int rt){    if (L <= l && r <= R)        return T[rt];    int mid = (r + l) >>1;    int ans=-1;    if(L<=mid) ans=max(ans,query(L,R,lson));    if(R>mid)  ans=max(ans,query(L,R,rson));    return ans;}int main(){    int n, m;    while (~scanf("%d%d",&n,&m))    {        char str[15];        int b,c;        Build(1, n, 1);        while (m--)        {            scanf("%s%d%d",str,&b,&c);            if (str[0] == 'U') Update(b, c, 1, n, 1);            if (str[0] == 'Q') printf("%d\n",query(b, c, 1, n, 1));        }    }    return 0;}

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