poj3468 A Simple Problem with Integers(线段树)

A Simple Problem with Integers
Time Limit: 5000MS   Memory Limit: 131072K
Total Submissions: 83200   Accepted: 25771
Case Time Limit: 2000MS

Description

You have N integers, A1A2, ... , AN. You need to deal with two kinds of operations. One type of operation is to add some given number to each number in a given interval. The other is to ask for the sum of numbers in a given interval.

Input

The first line contains two numbers N and Q. 1 ≤ N,Q ≤ 100000.
The second line contains N numbers, the initial values of A1A2, ... , AN. -1000000000 ≤ Ai ≤ 1000000000.
Each of the next Q lines represents an operation.
"C a b c" means adding c to each of AaAa+1, ... , Ab. -10000 ≤ c ≤ 10000.
"Q a b" means querying the sum of AaAa+1, ... , Ab.

Output

You need to answer all Q commands in order. One answer in a line.

Sample Input

10 5
1 2 3 4 5 6 7 8 9 10
Q 4 4
Q 1 10
Q 2 4
C 3 6 3
Q 2 4

Sample Output

4
55
9
15

Hint

The sums may exceed the range of 32-bit integers.

Source

POJ Monthly--2007.11.25, Yang Yi

题意:一行序列,每次操作把一个区间里的每个数都加上一个数,或者查询一个区间的和。
分析:一道模板题吧,就每次叠加就行了,只是注意数据范围int会超。

#include <iostream>
#include <cstdio>
#include <cstring>
#include <stack>
#include <queue>
#include <map>
#include <set>
#include <vector>
#include <cmath>
#include <algorithm>
using namespace std;
const double eps = 1e-6;
const double pi = acos(-1.0);
const int INF = 0x3f3f3f3f;
const int MOD = 1000000007;
#define ll long long
#define CL(a,b) memset(a,b,sizeof(a))
#define MAXN 100010

struct node
{
    int l,r;
    ll s,add;//add为每次加的数
}t[MAXN<<2];
int hh[MAXN];
int n,q;
ll ans;

void build(int l, int r, int i)
{
    t[i].l = l;
    t[i].r = r;
    t[i].add = 0;
    if(l == r) return ;
    int mid = (l+r)>>1;
    build(l, mid, i<<1);
    build(mid+1, r, i<<1|1);
    t[i].s = t[i<<1].s+t[i<<1|1].s;
}

void update(int l, int r, int add, int i)
{
    if(t[i].l>r || t[i].r<l) return ;
    if(t[i].l>=l && t[i].r<=r)
    {
        t[i].s += (t[i].r-t[i].l+1)*add;
        t[i].add += add;
        return ;
    }
    if(t[i].add)
    {
        t[i<<1].s += (t[i<<1].r-t[i<<1].l+1)*t[i].add;
        t[i<<1].add += t[i].add;
        t[i<<1|1].s += (t[i<<1|1].r-t[i<<1|1].l+1)*t[i].add;
        t[i<<1|1].add += t[i].add;
        t[i].add = 0;
    }
    update(l, r, add, i<<1);
    update(l, r, add, i<<1|1);
    t[i].s = t[i<<1].s+t[i<<1|1].s;
}

void query(int l, int r, int i)
{
    if(t[i].l>r || t[i].r<l) return ;
    if(t[i].l>=l && t[i].r<=r)
    {
        ans += t[i].s;
        return ;
    }
    if(t[i].add)
    {
        t[i<<1].s += (t[i<<1].r-t[i<<1].l+1)*t[i].add;
        t[i<<1].add += t[i].add;
        t[i<<1|1].s += (t[i<<1|1].r-t[i<<1|1].l+1)*t[i].add;
        t[i<<1|1].add += t[i].add;
        t[i].add = 0;
    }
    query(l, r, i<<1);
    query(l, r, i<<1|1);
    t[i].s = t[i<<1].s+t[i<<1|1].s;
}

int main()
{
    int a,b,c;
    ll k;
    char ch;
    while(scanf("%d%d",&n,&q)==2)
    {
        for(int i=1; i<=n; i++)
            scanf("%d",&hh[i]);
        build(1, n, 1);
        for(int i=1; i<=n; i++)
            update(i, i, hh[i], 1);
        while(q--)
        {
            getchar();
            scanf("%c",&ch);
            if(ch == 'C')
            {
                scanf("%d%d%d",&a,&b,&c);
                update(a, b, c, 1);
            }
            if(ch == 'Q')
            {
                ans = 0;
                scanf("%d%d",&a,&b);
                query(a, b, 1);
                printf("%lld\n",ans);
            }
        }
    }
    return 0;
}


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