Submission #369820

#	Time	Username	Problem	Language	Result	Execution time	Memory
369820		AdamGS	Xor Sort (eJOI20_xorsort)	C++14	25 / 100	14 ms	1768 KiB

xorsort

#include<bits/stdc++.h>
using namespace std;
typedef long long ll;
#define rep(a, b) for(ll a = 0; a < (b); ++a)
#define lg(a) (!a?0:64-__builtin_clzll(a))
#define st first
#define nd second
#define pb push_back
const ll LIM=1e3+7;
ll T[LIM], n, s, l=1;
vector<pair<ll,ll>>ans;
void s1() {
    rep(i, n) rep(j, n-i-1) {
        if(T[j]>T[j+1]) {
            swap(T[j], T[j+1]);
            ans.pb({j, j+1});
            ans.pb({j+1, j});
            ans.pb({j, j+1});
        }
    }
}
void s2() {
    for(int i=20; i; --i) {
        int p=0;
        rep(j, n-l) {
            if(lg(T[j])==i) {
                p=1;
                if(lg(T[j])!=lg(T[j+1])) {
                    ans.pb({j+1, j});
                    T[j+1]^=T[j];
                }
                ans.pb({j, j+1});
                T[j]^=T[j+1];
            }
        }
        l+=p;
    }
}
int main() {
    ios_base::sync_with_stdio(0); cin.tie(0);
    cin >> n >> s;
    rep(i, n) cin >> T[i];
    if(s==1) s1(); else s2();
    cout << ans.size() << '\n';
    for(auto i : ans) cout << i.st+1 << " " << i.nd+1 << '\n';
}

• Subtask 1: 25 / 25
• Subtask 2: 0 / 35
• Subtask 3: 0 / 40