Submission #838044

#	Time	Username	Problem	Language	Result	Execution time	Memory
838044		Kerim	Wiring (IOI17_wiring)	C++17	100 / 100	47 ms	11812 KiB

wiring

#include "wiring.h"
#include "bits/stdc++.h"
#define ff first 
#define ss second
#define ll long long
using namespace std;
const ll B = 1e16;
void make(vector<ll>&v, int sz){
	v.resize(sz);
	for (int i = 0; i < sz; i++) 
		v[i] = B;
}
ll min_total_length(vector<int> r, vector<int> b) {
	vector<pair<int,int> > v;
	vector<vector<int> > d;
	vector<int> sz; 
	for (auto x: r) v.push_back({x, 0});
	for (auto x: b) v.push_back({x, 1});
	sort(v.begin(), v.end());
	for (int i = 0; i < v.size(); i++){
		int j = i;
		vector<int> g{-1};
		while (j < v.size() and v[i].ss == v[j].ss)
			g.push_back(v[j++].ff);
		d.push_back(g);
		sz.push_back(j - i);
		i = j - 1;
	}
	int n = d.size();
	vector<ll> dp, odp;
	vector<ll> pre, suf, suf_k, pref_k;
	make(dp, sz[0]+1);
	dp[0] = 0;
	for (int i = 1; i < n; i++){
		swap(odp, dp);
		make(dp, sz[i]+1);
		dp[0] = odp[sz[i-1]];
		pre.resize(sz[i]+1);
		suf.resize(sz[i-1]+2);
		suf_k.resize(sz[i-1]+2);
		pref_k.resize(sz[i-1]+2);
		for (int j = 1; j <= sz[i]; j++)
			pre[j] = pre[j-1] + d[i][j];
		suf[sz[i-1]+1] = 0;
		suf_k[sz[i-1]+1] = B;
		pref_k[0] = B;
		for (int k = sz[i-1]; k >= 1; k--){
			suf[k] = suf[k+1] + d[i-1][k];
			suf_k[k] = min(suf_k[k+1], min(odp[k-1], odp[k])+d[i-1][sz[i-1]]*1LL*(sz[i-1]-k+1) - suf[k]);
		}
		for (int k = 1; k <= sz[i-1]; k++) 
			pref_k[k] = min(pref_k[k-1], min(odp[k-1], odp[k])+(d[i][1]-d[i-1][sz[i-1]])*1LL*(sz[i-1]-k+1)+d[i-1][sz[i-1]]*1LL*(sz[i-1]-k+1)-suf[k]);
		for (int j = 1; j <= sz[i]; j++){
			int p = sz[i-1]+1-j;
			if (p >= 1)
				dp[j] = pre[j]-j*1LL*d[i][1] + pref_k[p-1];
			dp[j] = min(dp[j], (d[i][1]-d[i-1][sz[i-1]])*1LL*j+pre[j]-j*1LL*d[i][1] + suf_k[max(1, p)]);
		}
	}
	return dp[sz[n-1]];
}

Compilation message (stderr)

wiring.cpp: In function 'long long int min_total_length(std::vector<int>, std::vector<int>)':
wiring.cpp:20:20: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<std::pair<int, int> >::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   20 |  for (int i = 0; i < v.size(); i++){
      |                  ~~^~~~~~~~~~
wiring.cpp:23:12: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<std::pair<int, int> >::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   23 |   while (j < v.size() and v[i].ss == v[j].ss)
      |          ~~^~~~~~~~~~

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