Submission #512823

#	Time	Username	Problem	Language	Result	Execution time	Memory
512823		kevinxiehk	The Big Prize (IOI17_prize)	C++17	20 / 100	129 ms	8032 KiB

prize

#include "prize.h"
#include "bits/stdc++.h"
using namespace std;
int ddd = 1;
int fen[200005][10];
int corr[10];
int n;
unordered_map<int, int> aaa;
void add(int id, int x, int k) {
    id++;
    while(id <= n) {
        fen[id][k] += x;
        id += (id & (-id));
    }
}
int sum(int id, int k) {
    int ans = 0;
    id++;
    while(id > 0) {
        ans += fen[id][k];
        id -= (id & (-id));
    }
    return ans;
}    
int getbefore(int id, int k) {
    int t = 0;
    for(int i = 1; i < ddd; i++) {
        if(corr[i] < k) t += sum(id, i);
    }
    return t;
}
void add_val(int a, int k) {
    if(aaa[k] == 0) {corr[ddd] = k; aaa[k] = ddd++;}
    add(a, 1, aaa[k]);
}
int find_best(int N) {
    n = N;
    int now = 0;
    int dx = 0;
    int sign = 1;
    // int t = 100;
    while(1) {
        cerr << now << '\n';
        vector<int> res = ask(now);
		if(res[0] + res[1] == 0) return now;
        if(res[0] == getbefore(now, res[0] + res[1])) {
            sign = 1;
            dx *= 2;
            if(dx == 0) dx++;
        }
        else {
            sign = -1;
            dx /= 2;
            if(dx == 0) dx++;
        }
        add_val(now, res[0] + res[1]);
        if(sign == 1) dx = min(dx, n - 1 - now);
        else dx = min(dx, now);
        now += dx * sign;
    }
	// for(int i = 0; i < n; i++) {
	// 	vector<int> res = ask(i);
	// 	if(res[0] + res[1] == 0)
	// 		return i;
	// }
	return 0;
}

• Subtask 1: 20 / 20
• Subtask 2: 0 / 80