Submission #1117707

#	Time	Username	Problem	Language	Result	Execution time	Memory
1117707		vjudge1	Kangaroo (CEOI16_kangaroo)	C++17	0 / 100	423 ms	524288 KiB

kangaroo

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

int main(){
    freopen("kangaroo.in","r",stdin);
    freopen("kangaroo.out", "w",stdout);
    int n,st,ft;
    cin >> n >> st >> ft;
    vector<int> sira;
    for(int i=1;i<=n;++i)sira.push_back(i);
    int cnt=0;
    do{
        if(sira[0] != st || sira[n-1] != ft)continue;
        bool flag;
        flag = (sira[0] < sira[1]);
        bool val = 1;
        for(int i=1;i<n-1;++i){
            if(flag ^ (sira[i] < sira[i+1])){
            flag ^= 1;
            continue;
            }
            val = 0;
            continue;
        }
        cnt += val;
    }while(next_permutation(sira.begin(),sira.end()));
    cout << cnt;
}

Compilation message (stderr)

kangaroo.cpp: In function 'int main()':
kangaroo.cpp:5:12: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
    5 |     freopen("kangaroo.in","r",stdin);
      |     ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~
kangaroo.cpp:6:12: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
    6 |     freopen("kangaroo.out", "w",stdout);
      |     ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~

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