oj.uz

Submission #7919

# Submission time Handle Problem Language Result Execution time Memory
7919 2014-08-25T08:28:57 Z gs14004 허수아비 (JOI14_scarecrows) C++
100 / 100
 1660 ms 18604 KB 
#include <cstdio>
#include <cstring>
#include <algorithm>
#include <set>
using namespace std;
typedef pair<int,int> pi;

struct pt{int x,y;}pos[200005];
int cmp1(pt a, pt b){return a.x<b.x;}
int cmp2(pt a, pt b){return a.y<b.y;}

int a[200005],n;

int lim, tree[270000];
void initTree(){
    for(lim = 1; lim <= n+1; lim <<= 1);
    memset(tree,0,sizeof(tree));
}
void add(int x){
    while (x <= lim) {
        tree[x]++;
        x += x & -x;
    }
}
int sum(int x){
    int res = 0;
    while (x) {
        res += tree[x];
        x -= x & -x;
    }
    return res;
}

long long f(int s, int e){
    long long res = 0;
    if(e - s < 500){
        for (int i=s; i<=e; i++) {
            int lower=a[i];
            int upper=1987654321;
            for (int j=i+1; j<=e; j++) {
                if(upper>a[j] && a[j]>lower){
                    upper=a[j];
                    res++;
                }
            }
        }
        return res;
    }
    int m = (s+e)/2;
    res = f(s,m) + f(m+1,e);
    
    initTree();
    set<pi> s_left, s_right, s_right_old;
    set<pi> ::iterator it,it2;
    int lim;
    
    for (int i=m; i>=s; i--) {
        it = s_left.upper_bound(pi(a[i],0));
        if(it == s_left.end()) lim = n+1;
        else lim = (*it).first - 1;
        s_left.insert(pi(a[i],lim));
    }
    
    for (int i=m+1; i<=e; i++) {
        it = s_right_old.upper_bound(pi(a[i],0));
        if(it == s_right_old.begin()) lim = -1;
        else{
            it--;
            lim = (*it).first;
        }
        s_right_old.insert(pi(a[i],lim));
        s_right.insert(pi(lim,a[i]));
    }
    
    s_left.insert(pi(1e6,1e6));
    s_right.insert(pi(1e6,1e6));
    it = s_left.begin();
    it2 = s_right.begin();
    
    for (int i=s; i<=e; i++) {
        if((*it).first < (*it2).first){
            res += sum((*it).second) - sum((*it).first - 1);
            it++;
        }
        else{
            add((*it2).second);
            it2++;
        }
    }
    return res;
}

int main(){
    scanf("%d",&n);
    for (int i=0; i<n; i++) {
        scanf("%d %d",&pos[i].x,&pos[i].y);
    }
    sort(pos,pos+n,cmp2);
    for (int i=0; i<n; i++) {
        pos[i].y = i+1;
    }
    sort(pos,pos+n,cmp1);
    for (int i=0; i<n; i++) {
        a[i] = pos[i].y;
    }
    long long r = f(0,n-1);
    printf("%lld",r);
}

Subtask #1
5.0 / 5.0

# Verdict Execution time Memory Grader output
1 Correct 0 ms 4612 KB Output is correct
2 Correct 0 ms 4612 KB Output is correct
3 Correct 0 ms 4612 KB Output is correct
4 Correct 0 ms 4612 KB Output is correct
5 Correct 0 ms 4612 KB Output is correct
6 Correct 0 ms 4612 KB Output is correct
7 Correct 0 ms 4612 KB Output is correct
8 Correct 0 ms 4612 KB Output is correct
9 Correct 0 ms 4612 KB Output is correct
10 Correct 0 ms 4612 KB Output is correct

Subtask #2
10.0 / 10.0

# Verdict Execution time Memory Grader output
1 Correct 12 ms 4876 KB Output is correct
2 Correct 16 ms 4876 KB Output is correct
3 Correct 8 ms 4876 KB Output is correct
4 Correct 8 ms 4876 KB Output is correct
5 Correct 12 ms 4876 KB Output is correct
6 Correct 16 ms 4876 KB Output is correct
7 Correct 16 ms 4876 KB Output is correct
8 Correct 12 ms 4876 KB Output is correct
9 Correct 12 ms 4876 KB Output is correct
10 Correct 16 ms 4876 KB Output is correct
11 Correct 16 ms 4876 KB Output is correct
12 Correct 12 ms 4876 KB Output is correct

Subtask #3
85.0 / 85.0

# Verdict Execution time Memory Grader output
1 Correct 1056 ms 18604 KB Output is correct
2 Correct 1644 ms 18604 KB Output is correct
3 Correct 1096 ms 18604 KB Output is correct
4 Correct 960 ms 18604 KB Output is correct
5 Correct 1216 ms 18604 KB Output is correct
6 Correct 1396 ms 18604 KB Output is correct
7 Correct 1556 ms 18604 KB Output is correct
8 Correct 1652 ms 18604 KB Output is correct
9 Correct 1100 ms 18604 KB Output is correct
10 Correct 1144 ms 18604 KB Output is correct
11 Correct 1388 ms 18604 KB Output is correct
12 Correct 1604 ms 18604 KB Output is correct
13 Correct 1644 ms 18604 KB Output is correct
14 Correct 956 ms 18604 KB Output is correct
15 Correct 1412 ms 18604 KB Output is correct
16 Correct 1660 ms 18604 KB Output is correct
17 Correct 824 ms 13720 KB Output is correct
18 Correct 1572 ms 18604 KB Output is correct
19 Correct 1536 ms 18604 KB Output is correct
20 Correct 1492 ms 18604 KB Output is correct