Submission #545027

#	Time	Username	Problem	Language	Result	Execution time	Memory
545027		Asymmetry	Collecting Stamps 3 (JOI20_ho_t3)	C++17	100 / 100	52 ms	68160 KiB

ho_t3

//Autor: Bartłomiej Czarkowski
#include <bits/stdc++.h>
using namespace std;
#ifdef DEBUG
template<class A,class B>auto&operator<<(ostream&o,pair<A,B>p){return o<<'('<<p.first<<", "<<p.second<<')';}
template<class T>auto operator<<(ostream&o,T x)->decltype(x.end(),o){o<<'{';int i=0;for(auto e:x)o<<(", ")+2*!i++<<e;return o<<'}';}
#define debug(x...) cerr<<"["#x"]: ",[](auto...$){((cerr<<$<<"; "),...);}(x),cerr<<'\n'
#else
#define debug(...) {}
#endif

typedef unsigned int unt;

const int N = 210;
int n, L, odp;
unt X[N];
unt T[N];
unt dp[N][N][N][2];

int main() {
	scanf("%d%d", &n, &L);
	for (int i = 1; i <= n; ++i) {
		scanf("%d", &X[i]);
	}
	X[n + 1] = L;
	for (int i = 1; i <= n; ++i) {
		scanf("%d", &T[i]);
	}
	for (int i = 0; i <= n + 1; ++i) {
		for (int j = 0; j <= n + 1; ++j) {
			for (int k = 0; k <= n; ++k) {
				dp[i][j][k][0] = dp[i][j][k][1] = 1e9 + 7;
			}
		}
	}
	dp[0][n + 1][0][0] = dp[0][n + 1][0][1] = 0;
	for (int l = 0; l <= n; ++l) {
		for (int r = n + 1; r > l + 1; --r) {
			for (int k = 0; k <= n; ++k) {
				dp[l][r][k][0] = min(dp[l][r][k][0], dp[l][r][k][1] + L - X[r] + X[l]);
				dp[l][r][k][1] = min(dp[l][r][k][1], dp[l][r][k][0] + L - X[r] + X[l]);
				//~ debug(l, r, k, dp[l][r][k][0], dp[l][r][k][1]);
				
				if (dp[l][r][k][0] + X[l + 1] - X[l] <= T[l + 1]) {
					odp = max(odp, k + 1);
					dp[l + 1][r][k + 1][0] = min(dp[l + 1][r][k + 1][0], dp[l][r][k][0] + X[l + 1] - X[l]);
				}
				else {
					dp[l + 1][r][k][0] = min(dp[l + 1][r][k][0], dp[l][r][k][0] + X[l + 1] - X[l]);
				}
				
				if (dp[l][r][k][1] + X[r] - X[r - 1] <= T[r - 1]) {
					odp = max(odp, k + 1);
					dp[l][r - 1][k + 1][1] = min(dp[l][r - 1][k + 1][1], dp[l][r][k][1] + X[r] - X[r - 1]);
				}
				else {
					dp[l][r - 1][k][1] = min(dp[l][r - 1][k][1], dp[l][r][k][1] + X[r] - X[r - 1]);
				}
			}
		}
	}
	printf("%d\n", odp);
	return 0;
}

Compilation message (stderr)

ho_t3.cpp: In function 'int main()':
ho_t3.cpp:21:7: warning: ignoring return value of 'int scanf(const char*, ...)' declared with attribute 'warn_unused_result' [-Wunused-result]
   21 |  scanf("%d%d", &n, &L);
      |  ~~~~~^~~~~~~~~~~~~~~~
ho_t3.cpp:23:8: warning: ignoring return value of 'int scanf(const char*, ...)' declared with attribute 'warn_unused_result' [-Wunused-result]
   23 |   scanf("%d", &X[i]);
      |   ~~~~~^~~~~~~~~~~~~
ho_t3.cpp:27:8: warning: ignoring return value of 'int scanf(const char*, ...)' declared with attribute 'warn_unused_result' [-Wunused-result]
   27 |   scanf("%d", &T[i]);
      |   ~~~~~^~~~~~~~~~~~~

• Subtask 1: 5 / 5
• Subtask 2: 10 / 10
• Subtask 3: 10 / 10
• Subtask 4: 75 / 75