Submission #1007834

#	Time	Username	Problem	Language	Result	Execution time	Memory
1007834		christinelynn	Lasers (NOI19_lasers)	C++17	100 / 100	69 ms	12160 KiB

lasers

#include <bits/stdc++.h>
using namespace std; 
#define int long long
#define ld long double
#define fi first 
#define se second 
#define pb push_back
#define pii pair<int,int>
#define piii pair<pair<int,int>,pair<int,int>>
#define pip pair<int,pair<int,int>>

signed main(){
    ios_base::sync_with_stdio(false); 
    cin.tie(NULL); 
    cout.tie(NULL); 
    int ans = 0; 
    int n, q; cin >> n >> q; 
    vector<pair<int,int>>v; 
    for(int i = 1; i <= q; i++){
        int x; cin >> x; 
        int a[x+5]; 
        int tmp = 0; 
        for(int i = 1; i <= x; i++){
            cin >> a[i]; tmp += a[i]; 
        }
        int rem = n - tmp; 
        int cnt = 0; 
        int last = 0; 
        for(int i = 1; i <= x; i++){
            last += a[i]; 
            int val = a[i] - rem; 
            if(val <= 0)continue; 
            v.pb({last-val+1,last}); 
        }
    }
    sort(v.begin(),v.end()); 
    int last = 0; 
    for(int i = 0; i < v.size(); i++){
        //cout << "here >> " << v[i].fi << " " << v[i].se << endl; 
        if(v[i].fi > last){
            ans += (v[i].se - v[i].fi + 1); 
            last = v[i].se; 
        }
        else if(v[i].se > last){
            ans += (v[i].se - last); 
            last = v[i].se; 
        }
    }
    cout << ans << endl; 
}   

Compilation message (stderr)

lasers.cpp: In function 'int main()':
lasers.cpp:27:13: warning: unused variable 'cnt' [-Wunused-variable]
   27 |         int cnt = 0;
      |             ^~~
lasers.cpp:38:22: warning: comparison of integer expressions of different signedness: 'long long int' and 'std::vector<std::pair<long long int, long long int> >::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   38 |     for(int i = 0; i < v.size(); i++){
      |                    ~~^~~~~~~~~~

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