제출 #407740

#	제출 시각	아이디	문제	언어	결과	실행 시간	메모리
407740		Kevin_Zhang_TW	커다란 상품 (IOI17_prize)	C++17	90 / 100	152 ms	7616 KiB

prize

#include <bits/stdc++.h>
using namespace std;
using ll = long long;
#define pb emplace_back
#define AI(i) begin(i), end(i)
template<class T> bool chmin(T &a, T b) { return b < a && (a = b, true); }
template<class T> bool chmax(T &a, T b) { return a < b && (a = b, true); }
#ifdef KEV
#define DE(args...) kout("[ " + string(#args) + " ] = ", args)
void kout() { cerr << endl; }
template<class T, class ...U> void kout(T a, U ...b) { cerr << a << ' ', kout(b...); }
template<class T> void debug(T l, T r) { while (l != r) cerr << *l << " \n"[next(l)==r], ++l; }
#else
#define DE(...) 0
#define debug(...) 0
#endif

#include "prize.h"

const int MAX_N = 300010;

vector<int> qry(int id) {
	static vector<int> mem[MAX_N];
	if (mem[id].size()) return mem[id];
	return mem[id] = ask(id);
}

int sum(int id) {
	return qry(id)[0] + qry(id)[1];
}

int find_best(int n) {

	int cnt = 1, m, h = 0;

	while (h < n) {
		while (sum(h) < cnt) {
			if (sum(h) == 0) return h;
			++h;
		}
		cnt = sum(h);

		int U = 1;
		while (h + U < n) {
			int p = min(n-1, h + (U<<1));
			if (sum(p) > cnt) {
				cnt = sum(m);
				break;
			}
			if (sum(p) < cnt || qry(p)[0] > qry(h)[0]) {
				U<<=1;
				break;
			}
			U <<= 1;
		}

		if (cnt != sum(h)) continue;

		int l = h, r = min(n-1, l + U), m;
		DE(l, r);

		while (l < r) {
			m = (l + r >> 1)+1;
			if (sum(m) > cnt) {
				cnt = sum(m);
				break;
			}
			if (sum(m) < cnt || qry(m)[0] > qry(h)[0]) {
				if (sum(m) == 0) return m;
				r = m-1;
			}
			else 
				l = m;
		}
		if (sum(h) != cnt) continue;
		h = l + 1;
	}
	assert(false);
}

컴파일 시 표준 에러 (stderr) 메시지

prize.cpp: In function 'int find_best(int)':
prize.cpp:14:17: warning: statement has no effect [-Wunused-value]
   14 | #define DE(...) 0
      |                 ^
prize.cpp:60:3: note: in expansion of macro 'DE'
   60 |   DE(l, r);
      |   ^~
prize.cpp:63:11: warning: suggest parentheses around '+' inside '>>' [-Wparentheses]
   63 |    m = (l + r >> 1)+1;
      |         ~~^~~
prize.cpp:47:14: warning: 'm' may be used uninitialized in this function [-Wmaybe-uninitialized]
   47 |     cnt = sum(m);
      |           ~~~^~~

• Subtask 1: 20 / 20
• Subtask 2: 70 / 80