Submission #62123

#	Time	Username	Problem	Language	Result	Execution time	Memory
62123		bazsi700	Kangaroo (CEOI16_kangaroo)	C++14	6 / 100	2058 ms	560 KiB

kangaroo

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

#define MOD 1000000007
#define ll long long int
#define vi vector<int>
#define vii vector< vector<int> >
#define PI 3.1415926535897932384626433832795
#define INF 9223372036854775807LL

ll ways[10];
bool used[10];
int n,s,f;

int solve(int pos, int did, int from) {
	if(did == n && pos == f) {
		return 1;
	}
	used[pos] = true;
	int ans = 0;
	if(from == -1) {
		for(int i = 1; i <= n; i++) {
			if(i != pos) {
				ans+= solve(i,did+1,(i < pos ? 1 : 0));
			}
		}
	} else if(from == 0) {
		for(int i = 1; i < pos; i++) {
			if(!used[i]) {
				ans+= solve(i,did+1,1);
			}
		}
	} else {
		for(int i = pos+1; i <= n; i++) {
			if(!used[i]) {
				ans+= solve(i,did+1,0);
			}
		}
	}
	used[pos] = false;
	return ans;
}

int main() {
	ios::sync_with_stdio(false);
	cin.tie(NULL);
	cin >> n >> s >> f;
	if(s > f) {
		swap(s,f);
	}
	cout << solve(s,1,-1);
	return 0;
}

• Subtask 1: 6 / 6
• Subtask 2: 0 / 30
• Subtask 3: 0 / 15
• Subtask 4: 0 / 49