Submission #406059

#	Time	Username	Problem	Language	Result	Execution time	Memory
406059		maomao90	The short shank; Redemption (BOI21_prison)	C++17	35 / 100	163 ms	61252 KiB

prison

#include <bits/stdc++.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 4005

int n, d, t;
int ti[MAXN];
int cost[MAXN][MAXN];
ll dp[MAXN][MAXN];

void dnc(int i, int lo, int hi, int optl, int optr) {
	if (lo > hi) return;
	int j = lo + hi >> 1;
	int opt = -1;
	dp[i][j] = LINF;
	REP (k, optl, min(optr + 1, j)) {
		if (dp[i][j] > dp[i - 1][k] + cost[k + 1][j]) {
			dp[i][j] = dp[i - 1][k] + cost[k + 1][j];
			opt = k;
		}
	}
	dnc(i, lo, j - 1, optl, opt);
	dnc(i, j + 1, hi, opt, optr);
}

int main() {
	scanf("%d%d%d", &n, &d, &t);
	REP (i, 1, n + 1) {
		scanf("%d", &ti[i]);
	}
	REP (i, 1, n + 1) {
		ll r = -1;
		int cur = 0;
		REP (j, i, n + 1) {
			if (t >= ti[j]) mxto(r, t - ti[j] + j);
			if (r >= j) cur++;
			cost[i][j] = cur;
		}
	}
	REP (i, 1, n + 1) {
		dp[0][i] = cost[1][i];
	}
	REP (i, 1, d + 1) {
		dnc(i, 1, n, 1, n);
	}
	printf("%lld\n", dp[d][n]);
	return 0;
}

Compilation message (stderr)

prison.cpp: In function 'void dnc(int, int, int, int, int)':
prison.cpp:34:13: warning: suggest parentheses around '+' inside '>>' [-Wparentheses]
   34 |  int j = lo + hi >> 1;
      |          ~~~^~~~
prison.cpp: In function 'int main()':
prison.cpp:48:7: warning: ignoring return value of 'int scanf(const char*, ...)' declared with attribute 'warn_unused_result' [-Wunused-result]
   48 |  scanf("%d%d%d", &n, &d, &t);
      |  ~~~~~^~~~~~~~~~~~~~~~~~~~~~
prison.cpp:50:8: warning: ignoring return value of 'int scanf(const char*, ...)' declared with attribute 'warn_unused_result' [-Wunused-result]
   50 |   scanf("%d", &ti[i]);
      |   ~~~~~^~~~~~~~~~~~~~

• Subtask 1: 15 / 15
• Subtask 2: 0 / 10
• Subtask 3: 20 / 20
• Subtask 4: 0 / 10
• Subtask 5: 0 / 25
• Subtask 6: 0 / 20