Submission #585498

#	Time	Username	Problem	Language	Result	Execution time	Memory
585498		messiuuuuu	Palembang Bridges (APIO15_bridge)	C++14	63 / 100	2052 ms	5748 KiB

bridge

#include<bits/stdc++.h>
#define task "A"
#define ll long long
#define ld long double
#define fi first
#define se second
#define pb push_back
using namespace std;
const int MAXN = 1e5 + 5;
const ll INF = 1e18 + 5;

int n, k;
struct TRoad
{
    char h, o;
    ll ph, po;
}a[MAXN];

vector<ll> num;

void Input()
{
    cin >> k >> n;
    for (int i = 1; i <= n; i++)
    {
        cin >> a[i].h >> a[i].ph >> a[i].o >> a[i].po;
        num.pb(a[i].ph);
        num.pb(a[i].po);
    }
}

ll Cal1(ll c1, ll c2)
{
    ll res = 0;
    for (int i = 1; i <= n; i++)
    {
        if (a[i].h == a[i].o)
        {
            res += abs(a[i].ph - a[i].po);
        } else
        {
            res += min(abs(a[i].ph - c1) + abs(a[i].po - c1) + 1, abs(a[i].ph - c2) + abs(a[i].po - c2) + 1);
        }
    }
    return res;
}

ll Cal(int p)
{
    if (k == 1)
    {
        return Cal1(p, -2e9);
    }
    ll res = INF;
    for (int i = lower_bound(num.begin(), num.end(), p + 1) - num.begin(); i < num.size(); i++)
    {
        res = min(res, Cal1(p, num[i]));
    }
    return res;
}

void Solve()
{
    sort(num.begin(), num.end());
    num.erase(unique(num.begin(), num.end()), num.end());

    //cout << Cal(4) << '\n';
    if (k == 1)
    {
        int l = 0, r = 1e9;
        while (l <= r)
        {
            int mid = (l + r) / 2;
            if (mid == 1e9)
                break;
            if (Cal(mid) > Cal(mid + 1))
            {
                l = mid + 1;
            }
            else
                r = mid - 1;
        }
        cout << Cal(l);
    } else
    {
        ll res = INF;
        for (int i = 0; i < num.size(); i++)
        {
            int l = num[i] + 1, r = 1e9;
            while (l <= r)
            {
                int mid = (l + r) / 2;
                if (mid == 1e9)
                    break;
                if (Cal1(num[i], mid) > Cal1(num[i], mid + 1))
                {
                    l = mid + 1;
                }
                else
                    r = mid - 1;
            }
            res = min(res, Cal1(num[i], l));
        }
        cout << res;
    }
}

int main()
{
    ios_base::sync_with_stdio(false);
    cin.tie(nullptr);
    if (fopen(task".INP","r"))
    {
        freopen(task".INP","r",stdin);
        //freopen(task".OUT","w",stdout);
    }
    Input();
    Solve();
}

Compilation message (stderr)

bridge.cpp: In function 'long long int Cal(int)':
bridge.cpp:55:78: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<long long int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   55 |     for (int i = lower_bound(num.begin(), num.end(), p + 1) - num.begin(); i < num.size(); i++)
      |                                                                            ~~^~~~~~~~~~~~
bridge.cpp: In function 'void Solve()':
bridge.cpp:87:27: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<long long int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   87 |         for (int i = 0; i < num.size(); i++)
      |                         ~~^~~~~~~~~~~~
bridge.cpp: In function 'int main()':
bridge.cpp:114:16: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
  114 |         freopen(task".INP","r",stdin);
      |         ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~

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