제출 #99785

#	제출 시각	아이디	문제	언어	결과	실행 시간	메모리
99785		arnold518	허수아비 (JOI14_scarecrows)	C++14	100 / 100	712 ms	67240 KiB

scarecrows

#include <bits/stdc++.h>
using namespace std;

typedef long long ll;
typedef pair<int, int> pii;
typedef pair<ll, ll> pll;

const int MAXN = 2e5;

struct Point
{
    int x, y;
    Point() {}
    Point(int x, int y) : x(x), y(y) {}
    bool operator < (const Point& p)
    {
        return x<p.x;
    }
};

int n;
ll ans;
Point arr[MAXN+10];
vector<int> xpos, ypos;
int xcoord[MAXN+10];

vector<vector<Point>> tree;

void update(int node, int tl, int tr, int x, int y)
{
    if(tl==tr) { tree[node]=vector<Point>(1, Point(x, y)); return; }
    int mid=tl+tr>>1;
    if(y<=mid) update(node*2, tl, mid, x, y);
    else update(node*2+1, mid+1, tr, x, y);

    while(!tree[node].empty() && tree[node].back().y<y) tree[node].pop_back();
    tree[node].push_back({x, y});
}

int last=-1, ret=0;
void query(int node, int tl, int tr, int l, int r)
{
    if(r<tl || tr<l) return;
    if(l<=tl && tr<=r)
    {
        if(tree[node].empty()) return;
        ret+=tree[node].end()-lower_bound(tree[node].begin(), tree[node].end(), Point(last, 0));
        last=max(last, tree[node].back().x);
        return;
    }
    int mid=tl+tr>>1;
    query(node*2+1, mid+1, tr, l, r);
    query(node*2, tl, mid, l, r);
}

int main()
{
    int i, j;
    scanf("%d", &n);
    for(i=0; i<n; i++)
    {
        scanf("%d%d", &arr[i].x, &arr[i].y);
        xpos.push_back(arr[i].x);
        ypos.push_back(arr[i].y);
    }
    sort(xpos.begin(), xpos.end());
    sort(ypos.begin(), ypos.end());

    for(i=0; i<n; i++)
    {
        arr[i].x=lower_bound(xpos.begin(), xpos.end(), arr[i].x)-xpos.begin()+1;
        arr[i].y=lower_bound(ypos.begin(), ypos.end(), arr[i].y)-ypos.begin()+1;
    }

    sort(arr, arr+n, [&](const Point& p, const Point& q)
    {
        return p.x<q.x;
    });

    tree.resize(n*4+10);

    for(i=0; i<n; i++)
    {
        last=-1, ret=0;
        query(1, 1, n, 1, arr[i].y);
        ans+=ret;
        update(1, 1, n, arr[i].x, arr[i].y);
    }

    printf("%lld", ans);
}

컴파일 시 표준 에러 (stderr) 메시지

scarecrows.cpp: In function 'void update(int, int, int, int, int)':
scarecrows.cpp:32:15: warning: suggest parentheses around '+' inside '>>' [-Wparentheses]
     int mid=tl+tr>>1;
             ~~^~~
scarecrows.cpp: In function 'void query(int, int, int, int, int)':
scarecrows.cpp:51:15: warning: suggest parentheses around '+' inside '>>' [-Wparentheses]
     int mid=tl+tr>>1;
             ~~^~~
scarecrows.cpp: In function 'int main()':
scarecrows.cpp:58:12: warning: unused variable 'j' [-Wunused-variable]
     int i, j;
            ^
scarecrows.cpp:59:10: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
     scanf("%d", &n);
     ~~~~~^~~~~~~~~~
scarecrows.cpp:62:14: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
         scanf("%d%d", &arr[i].x, &arr[i].y);
         ~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

• Subtask 1: 5 / 5
• Subtask 2: 10 / 10
• Subtask 3: 85 / 85