hdu1166(线段树)

题目连接:http://acm.hdu.edu.cn/showproblem.php?pid=1166

线段树功能:update:单点增减 query:区间求和

#pragma comment(linker,"/STACK:102400000,102400000")
#include <cstdio>
#include <cstring>
#include <string>
#include <cmath>
#include <iostream>
#include <algorithm>
#include <queue>
#include <cstdlib>
#include <stack>
#include <vector>
#include <set>
#include <map>
#define LL long long
#define mod 1000000007
#define inf 0x3f3f3f3f
#define N 50010
#define FILL(a,b) (memset(a,b,sizeof(a)))
#define lson l,m,rt<<1
#define rson m+1,r,rt<<1|1
using namespace std;

int sum[N<<2];
int a[N];
void Pushup(int rt)
{
    sum[rt]=sum[rt<<1]+sum[rt<<1|1];
}
void build(int l,int r,int rt)
{
    if(l==r)
    {
        sum[rt]=a[l];
        return;
    }
    int m=(l+r)>>1;
    build(lson);
    build(rson);
    Pushup(rt);
}
void update(int pos,int num,int l,int r,int rt)
{
    if(l==r)
    {
        sum[rt]+=num;
        return;
    }
    int m=(l+r)>>1;
    if(pos<=m)update(pos,num,lson);
    else update(pos,num,rson);
    Pushup(rt);
}
int query(int L,int R,int l,int r,int rt)
{
    if(L<=l&&r<=R)
    {
        return sum[rt];
    }
    int m=(l+r)>>1;
    int res=0;
    if(L<=m)res+=query(L,R,lson);
    if(m<R)res+=query(L,R,rson);
    return res;
}
int main()
{
    int t,n,cas=1;
    char op[10];
    scanf("%d",&t);
    while(t--)
    {
        scanf("%d",&n);
        for(int i=1;i<=n;i++)scanf("%d",&a[i]);
        build(1,n,1);//printf("%d ",sum[20]);
        printf("Case %d:
",cas++);
        while(scanf("%s",op)>0)
        {
            if(op[0]=='E')break;
            int a,b;
            scanf("%d%d",&a,&b);
            if(op[0]=='Q')
                printf("%d
",query(a,b,1,n,1));
            else if(op[0]=='A')
                update(a,b,1,n,1);
            else update(a,-b,1,n,1);
        }
    }
}
View Code
原文地址:https://www.cnblogs.com/lienus/p/4240093.html