Submission #783155

#	Time	Username	Problem	Language	Result	Execution time	Memory
783155		pera	Exam (eJOI20_exam)	C++17	25 / 100	59 ms	1904 KiB

exam

#include<bits/stdc++.h>
using namespace std;

#define int long long

const int N = 2e5 + 1;


main(){
	ios::sync_with_stdio(0);
	cin.tie(0),cout.tie(0);
	int n , oK = 1;cin >> n;
	vector<int> a(n + 1) , b(n + 1);
	for(int i = 1;i <= n;i ++){
		cin >> a[i];
	}
	for(int i = 1;i <= n;i ++){
		cin >> b[i];
		if(i != 1) oK &= (b[i] == b[i - 1]);
	}
	if(oK){
		int c = 0;
		for(int i = 1;i <= n;i ++){
			int cc = 0 , k = 0;
			while(a[i] <= b[i] && i <= n){
				if(a[i] == b[i]) k = 1;
				++ cc , ++ i; 
			}
			if(k) c += cc;
		}
		cout << c << endl;
	}else{
		oK = 1;
		for(int i = 2;i <= n;i ++){
			oK &= (a[i] > a[i - 1]);
		}
		if(oK){
			vector<int> dp(n + 1);
			dp[1] = (a[1] == b[1]);
			for(int i = 2;i <= n;i ++){
				int q = 0;
				for(int j = i;j >= 1;j --){
					q += (a[i] == b[j]);
					dp[i] = max(dp[i] , q + dp[j - 1]);
				}
				for(int j = 1;j <= i;j ++){
					dp[j] = max(dp[j] , dp[j - 1] + (a[i] == b[j]));
				}
			}
			cout << *max_element(dp.begin() , dp.end()) << endl;
		}
	}
}

Compilation message (stderr)

exam.cpp:9:1: warning: ISO C++ forbids declaration of 'main' with no type [-Wreturn-type]
    9 | main(){
      | ^~~~

• Subtask 1: 0 / 14
• Subtask 2: 12 / 12
• Subtask 3: 13 / 13
• Subtask 4: 0 / 23
• Subtask 5: 0 / 16
• Subtask 6: 0 / 22