Submission #1007555

#	Time	Username	Problem	Language	Result	Execution time	Memory
1007555		makanhulia	Lasers (NOI19_lasers)	C++17	10 / 100	28 ms	16960 KiB

lasers

#include <bits/stdc++.h>
using namespace std;
#pragma GCC optimize("Ofast")
#pragma GCC optimize("unroll-loops")

typedef long long ll;
const ll INF = 1e9;
const ll MOD = 998244353;
const ll MAXN = 5e5 + 5;
const ll LOG = 31;
#define vll vector <ll>
#define pll pair <ll, ll>
#define fi first
#define se second
#define endl '\n'

ll n, m;
ll b [MAXN], pf [MAXN], sf [MAXN];
vector <pll> v;
vll ans;

void solve(){
    cin >> n >> m;
    for(ll i = 1; i <= m; i++){
        ll z; cin >> z;
        for(ll j = 1; j <= z; j++) cin >> b[j];
        pf[0] = 0, sf[z+1] = 0;
        for(ll j = 1; j <= z; j++) pf[j] = pf[j-1] + b[j];
        for(ll j = z; j >= 1; j--) sf[j] = sf[j+1] + b[j];

        for(ll j = 1; j <= z; j++){
            ll l = pf[j-1]+1, r = n - sf[j+1];
            if(l+b[j]-1 >= r-b[j]+1) v.push_back({l+b[j]-1, r-b[j]+1});
        }
    }
    sort(v.begin(), v.end());
    // for(auto x : v){
    //     cout << x.se << " " << x.fi << endl;
    // }
    ll ans = 0;
    ll vl = -INF, vr = -INF;
    for(auto x : v){
        ll l = x.se, r = x.fi;
        if(l <= vr) vr = r;
        else{
            if(vr != -INF) ans += vr - vl + 1;
            vl = l, vr = r;
        }
    }
    if(vr != -INF) ans += vr - vl + 1;
    cout << ans << endl;
}

int main(){
    ios_base::sync_with_stdio(0); cin.tie(0); cout.tie(0);
    // ll t; cin >> t;
    // while(t--){
        solve();
    // }
}

• Subtask 1: 10 / 10
• Subtask 2: 0 / 14
• Subtask 3: 0 / 20
• Subtask 4: 0 / 21
• Subtask 5: 0 / 22
• Subtask 6: 0 / 13