Submission #140506

#	Time	Username	Problem	Language	Result	Execution time	Memory
140506		bazsi700	Shortcut (IOI16_shortcut)	C++14	0 / 100	21 ms	376 KiB

shortcut

#include <bits/stdc++.h>
#include "shortcut.h"
using namespace std;

#define MOD 1000000007
#define ll long long int
#define vi vector<int>
#define vii vector< vector<int> >
#define PI 3.1415926535897932384626433832795
#define INF 9223372036854775807LL
#define hashA 1257958787
#define hashB 1539500609
#define endl "\n"

ll pref[10005];
vector<int> l;
vector<int> d;
int n,c;

ll getdist(ll a, ll b) {
	if(a > b) {
		swap(a,b);
	}
	return pref[b]-pref[a];
}

ll getcost(int b1, int b2) {
	if(max(b1,b2) >= n) {
		return INF;
	}
	ll mx = 0;
	for(int v1 = 0; v1 < n; v1++) {
		for(int v2 = v1+1; v2 < n; v2++) {
			ll dist = getdist(v1,v2);
			dist = min(dist,getdist(v1,b1)+c+getdist(v2,b2));
			mx = max(mx,dist+d[v1]+d[v2]);
		}
	}
	return mx;
}

ll find_shortcut(int N, vector<int> L, vector<int> D, int C) {
	n = N;
	c = C;
	l = L;
	d = D;
	ll ans = 0;
	ll currdist = d[0];
	for(int i = 1; i < n; i++) {
		pref[i] = pref[i-1]+l[i-1];
	}/*
	for(int i = 1; i < n; i++) {
		currdist+= l[i-1];
		ans = max(ans,currdist+d[i]);
		currdist = max(currdist,(ll)d[i]);
	}*/
	ll mn = INF;
	for(int b1 = 0; b1 < n; b1++) {
		int b2l = b1+1;
		int b2r = n-1;
		while(b2l < b2r) {
			int b2 = (b2l+b2r)/2;
			ll val1 = getcost(b1,b2);
			ll val2 = getcost(b1,b2+1);
			if(val2 > val1) {
				b2r = b2;
			} else {
				b2l = b2+1;
			}
			mn = min(mn,val1);
			mn = min(mn,val2);
		}
		mn = min(mn,getcost(b1,b2l));
		mn = min(mn,getcost(b1,b2r));
	}
	return mn;
}

Compilation message (stderr)

shortcut.cpp: In function 'long long int find_shortcut(int, std::vector<int>, std::vector<int>, int)':
shortcut.cpp:47:5: warning: unused variable 'ans' [-Wunused-variable]
  ll ans = 0;
     ^~~
shortcut.cpp:48:5: warning: unused variable 'currdist' [-Wunused-variable]
  ll currdist = d[0];
     ^~~~~~~~

• Subtask 1: 0 / 9
• Subtask 2: 0 / 14
• Subtask 3: 0 / 8
• Subtask 4: 0 / 7
• Subtask 5: 0 / 33
• Subtask 6: 0 / 22
• Subtask 7: 0 / 4
• Subtask 8: 0 / 3