Educational Codeforces Round 46 (Rated for Div. 2) C. Covered Points Count

Bryce1010模板

http://codeforces.com/problemset/problem/1000/C

题意：问你从[l,r]区间的被多少条线覆盖，列出所有答案。

思路：类似括号匹配的做法

#include <bits/stdc++.h>

using namespace std;

#define ll long long

const ll MAXN=2e5+10;
struct Node
{
    ll num;
    ll dir;//0左1右
    //ll cnt;
}node[MAXN*2];
ll cnt[MAXN*2];

bool cmp(Node a,Node b)
{
    if(a.num!=b.num)return a.num<b.num;
    else return a.dir<b.dir;
}

int main()
{
    ll n;
    cin>>n;
    for(ll i=0;i<2*n;i++)
    {
        if(i&1)
        {
            cin>>node[i].num;
            node[i].dir=1;
        }
        else
        {
            cin>>node[i].num;
            node[i].dir=0;
        }
    }
    sort(node,node+2*n,cmp);
//    for(ll i=0;i<2*n;i++)
//        cout<<node[i].num<<" "<<node[i].dir<<endl;;

    ll tot=0;
    for(ll i=0;i<2*n;i++)
    {
        if(node[i].dir==0)//左
        {
            if(node[i-1].dir==0)
                cnt[tot]+=node[i].num-node[i-1].num;
            else if(node[i-1].dir==1)
                cnt[tot]+=node[i].num-node[i-1].num-1;
            tot++;
        }
        else//右
        {
            if(node[i-1].dir==1)
                cnt[tot]+=node[i].num-node[i-1].num;
            else
                cnt[tot]+=node[i].num-node[i-1].num+1;
            tot--;
        }

    }

    cout<<cnt[1];
    for(ll i=2;i<=n;i++)
        cout<<" "<<cnt[i];
    cout<<endl;

    return 0;
}