Submission #1215272

#	Time	Username	Problem	Language	Result	Execution time	Memory
1215272		Madhav_1608	Palembang Bridges (APIO15_bridge)	C++20	100 / 100	44 ms	9864 KiB

bridge

#include <iostream>
#include <stack>
#include <queue>
#include <string>
#include <algorithm>
#include <vector>
#include <map>
#include <set>
#include <climits>
#include <cmath>
#include <unordered_map>
#include <unordered_set>
#include <numeric>
#include <iomanip>
#include <cstring>
#include <stdio.h>
#include <assert.h>
#include <complex>
#include <array>
#include <utility>
using namespace std;
typedef long long ll;
typedef vector<int> vi;
typedef vector<string> vs;
typedef vector<long long> vll;
typedef pair<ll,ll> pll;
#define double long double
#define F first
#define S second
const double eps = 1e-12; 
#define FOR(i,a,b) for(long long i=a;i<b;i++)
#define all(v) v.begin(),v.end()
template <typename I>
void print(vector<I> &v){
    FOR(i,0,v.size()){cout << v[i] << " ";}
    cout << "\n";
}
ll gcd(ll a,ll b){
    if(a==0){return b;}
    else if(b==0){return a;}
    else if(a<b){return gcd(b%a,a);}
    else{return gcd(a%b,b);}
}
ll lcm(ll a,ll b){
    return (a/gcd(a,b))*b;
}
void setIO(string name = "") {
    freopen((name + ".in").c_str(), "r", stdin); // see /general/input-output
    freopen((name + ".out").c_str(), "w", stdout);
}
void init_code(){
    #ifndef ONLINE_JUDGE
    freopen("input.txt","r",stdin);
    freopen("output.txt","w",stdout);
    #endif
}
vll cost(ll n,vll &a,vll &b){
    priority_queue<ll> left; // including median
    priority_queue<ll,vll,greater<ll>> right; // excluding median
    ll suml = 0;
    ll sumr = 0;
    vll ans;
    if(a[0]<=b[0]) swap(a[0],b[0]);
    left.push(b[0]);
    right.push(a[0]);
    sumr += a[0];
    suml += b[0];
    ans.push_back(0);
    FOR(i,1,n){
        ll med = left.top();
        ans.push_back(sumr-suml);
        if(a[i]>med){
            if(b[i]>med){
                right.push(a[i]);
                right.push(b[i]);
                sumr += (a[i]+b[i]);
                left.push(right.top());
                suml += right.top();
                sumr -= right.top();
                right.pop();
            }
            else{
                right.push(a[i]);
                sumr += a[i];
                left.push(b[i]);
                suml += b[i];
            }
        }
        else{
            if(b[i]<=med){
                left.push(a[i]);
                left.push(b[i]);
                suml += (a[i]+b[i]);
                right.push(left.top());
                sumr += left.top();
                suml -= left.top();
                left.pop();
            }
            else{
                right.push(b[i]);
                sumr += b[i];
                left.push(a[i]);
                suml += a[i];
            }            
        }
    }
    ans.push_back(sumr-suml);
    return ans;
}
void solve(){
    // store very big numbers may mean log2.
    // A comparator must return false for two equal objects. Not doing so results in undefined behavior.
    ll k,n;
    cin >> k >> n;
    vll a;
    vll b;
    ll ans = 0;
    FOR(i,0,n){
        char p,q;
        ll s,t;
        cin >> p >> s >> q >> t;
        if(p==q){
            ans += abs(s-t);
        }
        else{
            a.push_back(s);
            b.push_back(t);
        }
    }
    n = a.size();
    if(n==0){
        cout << ans << "\n";
        return;
    }
    if(k==1){
        vll left = cost(n,a,b);
        cout << (ans+left[n]+n) << "\n";
    }
    else{
        vector<pll> c;
        FOR(i,0,n){
            c.push_back({a[i]+b[i],i});
        }
        sort(all(c));
        vll a1;
        vll b1;
        FOR(i,0,n){
            a1.push_back(a[c[i].S]);
            b1.push_back(b[c[i].S]);
        }
        vll left = cost(n,a1,b1);
        reverse(all(a1));
        reverse(all(b1));
        vll right = cost(n,a1,b1);
        ll curr_ans = 1e16;
        FOR(i,0,n+1){
            curr_ans = min(curr_ans,left[i]+right[n-i]);
        }
        cout << (ans+curr_ans+n) << "\n";
    }
}

signed main(){
    //setIO
    ios::sync_with_stdio(0);
    cin.tie(0);
    cout.tie(0);
    // init_code();
    ll t=1;
    // cin >> t;
    while(t--){
        solve();
    }
    return 0;
}

Compilation message (stderr)

bridge.cpp: In function 'void setIO(std::string)':
bridge.cpp:48:12: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   48 |     freopen((name + ".in").c_str(), "r", stdin); // see /general/input-output
      |     ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
bridge.cpp:49:12: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   49 |     freopen((name + ".out").c_str(), "w", stdout);
      |     ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
bridge.cpp: In function 'void init_code()':
bridge.cpp:53:12: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   53 |     freopen("input.txt","r",stdin);
      |     ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~
bridge.cpp:54:12: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   54 |     freopen("output.txt","w",stdout);
      |     ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~

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