Submission #430924

#	Time	Username	Problem	Language	Result	Execution time	Memory
430924		Mazaalai	Wiring (IOI17_wiring)	C++14	0 / 100	34 ms	8736 KiB

wiring

#include "wiring.h"
#include <bits/stdc++.h>

typedef long long ll;
#define ff first
#define ss second

using namespace std;
vector <pair <ll, int> > all;
const int BLUE = 0;
const int RED = 1;
const ll INF = 1e10;
ll dist(ll a, ll b) {
    return abs(a - b);
}
const int N = 2e5 + 5;
vector <ll> pre(N), dp(N, INF);
ll sum(int a, int b) {
    // cout << "SUM: " << a << ' ' << b << '\n';
    return pre[a] - (b >= 0 ? pre[b] : 0);
}
long long min_total_length(vector<int> r, vector<int> b) {
    int n = r.size() + b.size();
    int color = RED;
    if (b[0] < r[0]) color = BLUE;
    all.push_back({-INF, 1-color});
    color = RED;
    if (b.back() > r.back()) color = BLUE;
    all.push_back({INF, 1-color});
    for (auto el : r) all.push_back({el, RED});
    for (auto el : b) all.push_back({el, BLUE});
    sort(all.begin(), all.end());
    for (int i = 1; i <= n; i++) {
        pre[i] = pre[i - 1] + all[i].ff;
        // cout << pre[i] << ' ';
    }
    // cout << "\n";
    dp[0] = 0;
    int pastSt = 1;
    for (int i = 1; i <= n; i++) {
        int j = i; 
        while(j + 1 <= n && all[j+1].ss == all[i].ss) j++;
        for (int k = pastSt; k < i; k++) {
            dp[k] = min(dp[k], dp[k-1] + dist(all[i].ff, all[k].ff));
        }
		int a, b;
        for (a = i, b = i-1; a <= j && b >= pastSt; a++, b--) {
			int k = a - i + 1;
            int curVal = (k * all[i].ff - sum(i-1, b-1)) + (sum(a, i-1) - k*all[i].ff);
            dp[a] = min(dp[a], dp[b-1] + curVal);
        }
		for (int k = a; k <= j; k++) {
			dp[k] = min(dp[k], dp[k-1] + dist(all[k].ff, all[i-1].ff));
		}
        // cout << pastSt << ' ' << i << ' ' << j << '\n';
        pastSt = i;
        i = j;
    }
	// for (int k = 1; k <= n; k++) {
	// 	cout << dp[k] << ' ';
	// }
	// cout << '\n';
    return dp[n];
}

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