Submission #170576

#	Time	Username	Problem	Language	Result	Execution time	Memory
170576		Swan	Palembang Bridges (APIO15_bridge)	C++14	0 / 100	2 ms	384 KiB

bridge

#include <bits/stdc++.h>
#define stop system("pause")
#define stop2 char o; cin >> o
#define INP freopen("pcb.in","r",stdin)
#define OUTP freopen ("pcb.out","w",stdout)
#define int long long
using namespace std;

const int maxn = 1e5+228;

int up[maxn],down[maxn];
int prefup[maxn],prefdown[maxn];
int sufup[maxn],sufdown[maxn];
unordered_map<int,int> cntup,cntdown;
unordered_map<int,int> rl;

main(){
    ios_base::sync_with_stdio(0);
    int k,n; cin >> k >> n;
    int ans = 0;
    set<int> qwe;
    int all = 0;
    for(int i(0); i < n;i++){
        char p,q;
        int s,t;
        cin >> p >> s >> q >> t;
        if(p == q){
            ans+=abs(s-t);
            continue;
        }
        if(p == 'B'){
            swap(p,q);
            swap(s,t);
        }
        qwe.insert(s);
        qwe.insert(t);
        cntup[s]++;
        cntdown[t]++;
        all++;
    }
    int pnt = 0;
    for(auto&a : qwe){
        up[pnt]+=cntup[a];
        down[pnt]+=cntdown[a];
        rl[pnt] = a;
        pnt++;
    }
    int now1 = up[0];
    int now2 = down[0];
    for(int i(1); i < pnt;i++){
        prefup[i]=prefup[i-1];
        prefdown[i]=prefdown[i-1];
        prefup[i]+=now1*(rl[i]-rl[i-1]);
        prefdown[i]+=now2*(rl[i]-rl[i-1]);
        now1+=up[i];
        now2+=down[i];
        //cout << rl[i] << ' ' << i << ' ' << prefdown[i] << endl;
    }
    //cout << now1 << ' ' << now2 << endl;
    //cout << pnt << ' ' << prefup[pnt-1] << endl;
    now1 = up[pnt-1];
    now2 = down[pnt-1];
    for(int i(pnt-2); i >= 0;i--){
        sufup[i]=sufup[i+1];
        sufdown[i]=sufdown[i+1];
        sufup[i]+=now1*(rl[i+1]-rl[i]);
        sufdown[i]+=now2*(rl[i+1]-rl[i]);
        now1+=up[i];
        now2+=down[i];
    }
    int res = 1e15;
    for(int i(0); i < pnt;i++){
        //cout << rl[i] << ' ' << sufdown[i] << ' ' << sufup[i] << ' ' << prefdown[i] << ' ' << prefup[i] << endl;
        res = min(res,sufdown[i]+sufup[i]+prefdown[i]+prefup[i]);
    }
    cout << ans+all+res;
}

/*
1 5
B 0 A 4
B 1 B 3
A 5 B 7
B 2 A 6
B 1 A 7
*/

Compilation message (stderr)

bridge.cpp:17:6: warning: ISO C++ forbids declaration of 'main' with no type [-Wreturn-type]
 main(){
      ^

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