Submission #781241

#	Time	Username	Problem	Language	Result	Execution time	Memory
781241		GusterGoose27	Wiring (IOI17_wiring)	C++17	0 / 100	82 ms	56508 KiB

wiring

#include "wiring.h"

#include <bits/stdc++.h>

using namespace std;

typedef long long ll;
typedef pair<int, int> pii;

const int MAXN = 1e5+5;
const ll inf = 1e18;
ll dp[2][MAXN][7][2][2];
int nxt[MAXN][2];
int n;

int _abs(int v) {
	return v < 0 ? -v : v;
}

ll hsh(int i, int j, bool lmatch, bool rmatch) {
	return (ll) 4*i*n+4*j+2*lmatch+rmatch;
}

ll make_dp(int i, int j, bool lmatch, bool rmatch, vector<int> &r, vector<int> &b) {
	int cur = i;
	for (int _ = 0; _ < 3; _++) cur = nxt[cur][_&1];
	if (cur <= j) return inf;
	cur = j;
	for (int _ = 1; _ < 4; _++) cur = nxt[cur][_&1];
	if (cur <= i) return inf;
	int cost = _abs(r[i]-b[j]);
	if (i == r.size()-1 && j == b.size()-1) {
		return cost;
	}
	ll cur_hsh = hsh(i, j, lmatch, rmatch);
	ll dpval = (nxt[i][0] <= j) ? dp[0][i][j-nxt[i][0]][lmatch][rmatch] : dp[1][j][i-nxt[j][0]][lmatch][rmatch];
	if (dpval != 0) return dpval;
	ll ans = inf;
	if (lmatch) ans = min(ans, make_dp(i+1, j, 0, rmatch, r, b));
	ans = min(ans, make_dp(i+1, j, 0, 1, r, b)+cost);
	if (rmatch) ans = min(ans, make_dp(i, j+1, lmatch, 0, r, b));;
	ans = min(ans, make_dp(i, j+1, 1, 0, r, b)+cost);
	if (nxt[i][0] <= j) dp[0][i][j-nxt[i][0]][lmatch][rmatch] = ans;
	else dp[1][j][i-nxt[j][0]][lmatch][rmatch] = ans;
	// cerr << i << ' ' << j << ' ' << lmatch << ' ' << rmatch << ' ' << ans << '\n';
	return ans;
}

ll min_total_length(vector<int> r, vector<int> b) {
	n = r.size()+b.size();
	int i = 0;
	nxt[r.size()][0] = b.size();
	nxt[b.size()][1] = r.size();
	for (int j = 0; j < b.size(); j++) {
		while (i < r.size() && r[i] < b[j]) i++;
		nxt[j][1] = i;
	}
	int j = 0;
	for (int i = 0; i < r.size(); i++) {
		while (j < b.size() && b[j] < r[i]) j++;
		nxt[i][0] = j;
	}
	ll ans = make_dp(0, 0, 0, 0, r, b);
	// assert(dp.size() < 7*n);
	return ans;
}

Compilation message (stderr)

wiring.cpp: In function 'll make_dp(int, int, bool, bool, std::vector<int>&, std::vector<int>&)':
wiring.cpp:32:8: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   32 |  if (i == r.size()-1 && j == b.size()-1) {
      |      ~~^~~~~~~~~~~~~
wiring.cpp:32:27: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   32 |  if (i == r.size()-1 && j == b.size()-1) {
      |                         ~~^~~~~~~~~~~~~
wiring.cpp:35:5: warning: unused variable 'cur_hsh' [-Wunused-variable]
   35 |  ll cur_hsh = hsh(i, j, lmatch, rmatch);
      |     ^~~~~~~
wiring.cpp: In function 'll min_total_length(std::vector<int>, std::vector<int>)':
wiring.cpp:54:20: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   54 |  for (int j = 0; j < b.size(); j++) {
      |                  ~~^~~~~~~~~~
wiring.cpp:55:12: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   55 |   while (i < r.size() && r[i] < b[j]) i++;
      |          ~~^~~~~~~~~~
wiring.cpp:59:20: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   59 |  for (int i = 0; i < r.size(); i++) {
      |                  ~~^~~~~~~~~~
wiring.cpp:60:12: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   60 |   while (j < b.size() && b[j] < r[i]) j++;
      |          ~~^~~~~~~~~~

• Subtask 1: 0 / 7
• Subtask 2: 0 / 13
• Subtask 3: 0 / 10
• Subtask 4: 0 / 25
• Subtask 5: 0 / 45