Submission #924685

#	Time	Username	Problem	Language	Result	Execution time	Memory
924685		Dzadzo	Wiring (IOI17_wiring)	C++14	100 / 100	44 ms	8896 KiB

wiring

#include <bits/stdc++.h>
#include "wiring.h"
#define ll long long
#define pb push_back
#define S second
#define F first
#define pii pair<int,int>
#define vi vector <ll>
#define vvi vector <vi>
#define vvvi vector <vvi>
#define vp vector <pii>
#define vvp vector <vp>
#define vb vector <bool>
#define vvb vector <vb>;
#define INF LLONG_MAX
#define MOD 1000000007
#define MAXN 100000
using namespace std;
ll min_total_length(std::vector<int> r, std::vector<int> b){
	vp v;
	v.pb({0,0});
	for (auto x:r)v.pb(make_pair(x*1ll,-1*1ll));
	for (auto x:b)v.pb(make_pair(x*1ll,1ll));
	int n=v.size()-1;
	sort(v.begin()+1,v.end());
	vi dp(n+1,INF),p(n+1);
	dp[0]=0;
	for (int i=1;i<=n;i++){
		p[i]=p[i-1]+v[i].F;
	}
	int cur=1,prev=0;
	while (v[prev].S==v[prev+1].S)cur++;
	int ind;
	for (int i=cur+1;i<=n;i++){
		if (v[i].S!=v[i-1].S){
			ind=v[i-1].F;
			for (int j=i-cur;j<i;j++)if (dp[j-1]!=INF)dp[j]=min(dp[j],dp[j-1]+v[i].F-v[j].F);
			prev=cur;
			cur=0;
		}
		cur++;
		if (dp[i-1]!=INF)
		dp[i]=min(dp[i],dp[i-1]+v[i].F-ind);
		if (cur<=prev && dp[i-2*cur]!=INF)dp[i]=min(dp[i],dp[i-2*cur]+p[i]+p[i-2*cur]-2*p[i-cur]);
	}
	return dp[n];
}

Compilation message (stderr)

wiring.cpp: In function 'long long int min_total_length(std::vector<int>, std::vector<int>)':
wiring.cpp:43:34: warning: 'ind' may be used uninitialized in this function [-Wmaybe-uninitialized]
   43 |   dp[i]=min(dp[i],dp[i-1]+v[i].F-ind);
      |                                  ^~~

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