Submission #259366

#	Time	Username	Problem	Language	Result	Execution time	Memory
259366		shayan_p	Palembang Bridges (APIO15_bridge)	C++14	49 / 100	2092 ms	3056 KiB

bridge

// And you curse yourself for things you never done
 
#include<bits/stdc++.h>
 
#define F first
#define S second
#define PB push_back
#define sz(s) int((s).size())
#define bit(n,k) (((n)>>(k))&1)
 
using namespace std;
 
typedef long long ll;
typedef pair<int,int> pii;
 
const int maxn = 1e5 + 10, inf = 1e9 + 10;
const ll INF = 1e18;
 
ll sv[maxn];
 
vector<pii> vec;
 
int pt;
set<int> All;
ll ANS;
 
void restart(){
    vec.clear();
    pt = -inf;
    All.clear();
    ANS = INF;
}
ll calc(int pos){
    ll num = 0;
    for(pii p : vec){
	if(pos < p.F)
	    num+= p.F - pos;
	if(p.S < pos)
	    num+= pos - p.S;
    }
    return num;
}
ll add(int f, int s){
    pt = -inf;
    ANS = INF;
    
    All.insert(f), All.insert(s);
    vec.PB({f, s});
    while(true){
	auto it = All.upper_bound(pt);
	if(it == All.end())
	    break;
	int nw = *it;
	ll num = calc(nw);
	if(num < ANS)
	    ANS = num, pt = nw;
	else
	    break;	   
    }
    return ANS * 2;
}
 
int main(){
    ios_base::sync_with_stdio(false); cin.tie(0); cout.tie();
 
    int k, n;
    cin >> k >> n;
    ll sig = 0;
    vector<pii> inp;
    for(int i = 0; i < n; i++){
	char a, b;
	int l, r;
	cin >> a >> l >> b >> r;
	if(r < l)
	    swap(l, r);
	sig+= r-l;
	if(a != b){
	    sig++;
	    inp.PB({l, r});
	}
    }
    sort(inp.begin(), inp.end(), [](pii a, pii b){ return a.F + a.S < b.F + b.S; } );
    n = sz(inp);
 
    if(n == 0)
	return cout << sig << endl, 0;
    
    restart();
    for(int i = 0; i < n; i++){
	sv[i + 1] = add(inp[i].F, inp[i].S);
    }
    restart();    
    ll ans = INF;
    for(int i = n-1; i >= 0; i--){
	ans = min(ans, sig + sv[i] + add(-inp[i].S, -inp[i].F));
    }
    if(k == 1)
	ans = sig + sv[n];
    return cout << ans << endl, 0;
    
}

• Subtask 1: 8 / 8
• Subtask 2: 0 / 14
• Subtask 3: 9 / 9
• Subtask 4: 32 / 32
• Subtask 5: 0 / 37