Submission #1090687

#	Time	Username	Problem	Language	Result	Execution time	Memory
1090687		BigBadBully	Fire (BOI24_fire)	C++17	0 / 100	1 ms	348 KiB

Main

#include <bits/stdc++.h>
#define ff first
#define ss second
#define int long long
#define pii pair<int, int>
#define ff first
#define ss second
using namespace std;
const int inf = 1e17;
const int mod = 998244353;
 
 
int solve2(int n,int m,vector<pii> v)
{
    
    sort(v.begin(),v.end());
    {
    vector<bool> del(n);
    int maxi = 0;
    for (int i = 0; i < n;i ++)
    {
        if (v[i].ss <= maxi)
            del[i] = 1;
        maxi = max(maxi,v[i].ss);
    }
    vector<pii> neu;
    for (int i = 0; i < n; i++)
        if (!del[i])
            neu.push_back(v[i]);
    n = neu.size();
    v = neu;
    }
    {
    vector<bool> del(n);
    int mini = v[n-1].ss;
    for (int i = n-1; i >= 0;i--)
    {
        if (v[i].ff >= mini)
            del[i] = 1;
        mini = min(mini,v[i].ff);
    }
    vector<pii> neu;
    for (int i = 0; i < n; i++)
        if (!del[i])
            neu.push_back(v[i]);
    n = neu.size();
    v = neu;
    }
    for (int i = 0;i  < n; i++)
        if (v[i].ff > v[i].ss)
            v[i].ss+=m;
    for (int i = 0; i< n;i++)
        v[i].ss%=m;
    /*for (int i = 0; i < n; i++)
        cout << v[i].ff << ' ' << v[i].ss << '\n';*/
    {
        int bigie = 0;
        for (int i = 0; i < n; i++)
            if (v[i].ff > v[i].ss)
                bigie = max(bigie,v[i].ss);
        vector<bool> del(n);
        for (int i = 0; i < n; i++)
            if (v[i].ff < v[i].ss && v[i].ss < bigie)
                del[i] = 1;
        vector<pii> neu;
        for (int i = 0; i < n; i++)
            if (!del[i])
                neu.push_back(v[i]);
        n = neu.size();
        v = neu;        
    }
    int prev = v[0].ss;
    int used = 1;
    if (n==1)
    {
        return -1;
    }
    if (v[0].ff != 0)
    {
        
        return -1;
    }
    for (int i = 1; i < n; i++)
    {
        if (v[i].ff > prev)
        {
            used++;
            prev = v[i-1].ss;
            if (v[i].ff > prev)
            {
                
                return -1;
            }
        }
        if (prev != 0 && v[i].ss == 0)
        {
            used++;
            prev = inf;
            break;
        }
    }
    if(prev == inf)
    return used;
    else
    return -1;
    
}
 
signed main()
{
    ios_base::sync_with_stdio(false);
    cin.tie(0);
    cout.tie(0);
    int n,m;
    cin >> n >> m;
    vector<pii> v(n);
    for (int i = 0; i < n; i++)
        cin >> v[i].ff >> v[i].ss;
    cout << solve2(n,m,v) << endl;
}

• Subtask 1: 0 / 14
• Subtask 2: 0 / 17
• Subtask 3: 0 / 9
• Subtask 4: 0 / 13
• Subtask 5: 0 / 21
• Subtask 6: 0 / 26