HDOJ 1556 线段树

链接：

http://acm.hdu.edu.cn/showproblem.php?pid=1556

题解：

之前偷懒使用前缀和写的，最近要复习一下线段树，所以又用线段树写了一下

另外是时候修改一下自己的//head了

代码：

#include <map>
#include <set>
#include <cmath>
#include <queue>
#include <stack>
#include <cstdio>
#include <string>
#include <vector>
#include <cstdlib>
#include <cstring>
#include <sstream>
#include <iostream>
#include <algorithm>
#include <functional>
using namespace std;
#define rep(i,a,n) for (int i=a;i<n;i++)
#define per(i,a,n) for (int i=n-1;i>=a;i--)
#define all(x) (x).begin(),(x).end()
#define pb push_back
#define mp make_pair
#define lson l,m,rt<<1  
#define rson m+1,r,rt<<1|1 
typedef long long ll;
typedef vector<int> VI;
typedef pair<int, int> PII;
const ll MOD = 1e9 + 7;
const int INF = 0x3f3f3f3f;
const int MAXN = 2e5 + 7;
// head

int n;
int tree[MAXN << 2], lazy[MAXN << 2];

void pushdown(int rt) {
    if (lazy[rt] != 0) {
        tree[rt << 1] += lazy[rt];
        tree[rt << 1 | 1] += lazy[rt];
        lazy[rt << 1] += lazy[rt];
        lazy[rt << 1 | 1] += lazy[rt];
        lazy[rt] = 0;
    }
}

void update(int L, int R, int l, int r, int rt) {
    if (L <= l && r <= R) {
        tree[rt]++;
        lazy[rt]++;
        return;
    }
    pushdown(rt);
    int m = (l + r) >> 1;
    if (L <= m) update(L, R, lson);
    if (R > m) update(L, R, rson);
}

int query(int k, int l, int r, int rt) {
    if (l == r) return tree[rt];
    pushdown(rt);
    int m = (l + r) >> 1;
    if (k <= m) query(k, lson);
    else query(k, rson);
}

int main() {
    while (cin >> n, n) {
        memset(tree, 0, sizeof(tree));
        memset(lazy, 0, sizeof(lazy));
        rep(i, 0, n) {
            int a, b;
            scanf("%d%d", &a, &b);
            update(a, b, 1, n, 1);
        }
        cout << query(1, 1, n, 1);
        rep(i, 2, n + 1) printf(" %d", query(i, 1, n, 1));
        cout << endl;
    }
    return 0;
}