Submission #406223

#TimeUsernameProblemLanguageResultExecution timeMemory
406223maomao90A Difficult(y) Choice (BOI21_books)C++17
50 / 100
218 ms584 KiB
#include <bits/stdc++.h> 
#include "books.h"
using namespace std;

#define mnto(x, y) x = min(x, (__typeof__(x)) y)
#define mxto(x, y) x = max(x, (__typeof__(x)) y)
#define REP(i, s, e) for (int i = s; i < e; i++)
#define RREP(i, s, e) for (int i = s; i >= e; i--)
typedef long long ll;
typedef long double ld;
#define MP make_pair
#define FI first
#define SE second
typedef pair<int, int> ii;
typedef pair<ll, ll> pll;
#define MT make_tuple
typedef tuple<int, int, int> iii;
#define ALL(_a) _a.begin(), _a.end()
#define pb emplace_back
typedef vector<int> vi;
typedef vector<ii> vii;

#define INF 1000000005
#define LINF 1000000000000000005
#define MOD 1000000007
#define MAXN 100005

ll x[MAXN];
int todo[15];

void solve(int n, int k, ll a, int s) {
	if (s == n) {
	REP (i, 1, n + 1) {
		x[i] = skim(i);
	}
	REP (i, 1, n + 1) {
		REP (j, i + 1, n + 1) {
			ll tmp = x[i] + x[j];
			ll rem = 2 * a - tmp;
			if (rem <= 0) continue;
			int lower = upper_bound(x + 1, x + n + 1, rem) - x - 1;
			if (lower == 0) continue;
			while (lower == i || lower == j) lower--;
			if (lower <= 0) continue;
			if (x[i] + x[j] + x[lower] >= a) {
				vi ans = {i, j, lower};
				answer(ans);
				return;
			}
		}
	}
	impossible();
	return;
	}
	ll small = 0;
	REP (i, 1, k + 1) {
		x[i] = skim(i);
		small += x[i];
	}
	ll big = 0;
	RREP (i, n, n - k + 1) {
		if (x[i] == 0) x[i] = skim(i);
		big += x[i];
	}
	if (small > 2 * a) {
	   	impossible();
		return;
	} else if (big < a) {
		impossible();
		return;
	}
	ll lo = 0, hi = (ll) (n - k) * k, mid;
	while (lo <= hi) {
		mid = hi + lo >> 1;
		ll tmp = mid;
		RREP (i, k, 1) {
			ll sub = min(tmp, (ll) n - k);
			todo[i] = i + sub;
			tmp -= sub;
		}
		ll sum = 0;
		REP (i, 1, k + 1) {
			if (x[todo[i]] == 0) x[todo[i]] = skim(todo[i]);
			sum += x[todo[i]];
		}
		if (sum < a) {
			lo = mid + 1;
		} else if (sum > 2 * a) {
			hi = mid - 1;
		} else {
			vi ans;
			REP (i, 1, k + 1) {
				ans.pb(todo[i]);
			}
			answer(ans);
			return;
		}
	}
	impossible();
}

Compilation message (stderr)

books.cpp: In function 'void solve(int, int, ll, int)':
books.cpp:74:12: warning: suggest parentheses around '+' inside '>>' [-Wparentheses]
   74 |   mid = hi + lo >> 1;
      |         ~~~^~~~
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