Submission #845921

---

Source Code Expand

#include <bits/stdc++.h>

#define ll long long
#define F first
#define S second
using namespace std;

template <class T, class P>
ostream &operator << (ostream &out, pair<T, P> &a){
    out << a.F << " " << a.S;
    return out;
}

template <class T>
ostream &operator << (ostream &out, vector <T> &a){
    for(auto &x : a)out << x << ' ';
    return out;
}

template <class T>
ostream &operator << (ostream &out, set <T> &a){
    for(auto &x : a) out << x << ' ';
    return out;
}

template <class T, class P>
ostream &operator << (ostream &out, map <T, P> &a){
    for(auto &x : a) out << x.F << " " << x.S << endl;
    return out;
}
const int N = 1e5 + 10;
const ll INF = 1e9 + 7;

int n;
string s;
ll t[N], d[N];
ll ans;
map <ll, ll> mp;

void solution(){
    int cnt = 0;
    cin >> n;
    for(int i = 1; i <= n; i++){
        cin >> t[i];
        d[i] = t[i];
    }
    sort(d + 1, d + 1 + n);
    for(int i = 1; i <= n; i++){
        mp[d[i]] = i;
    }
    for(int i = 1; i <= n; i++){
        if(abs(i - mp[t[i]]) % 2 == 1)cnt++;
    }
    cout << cnt / 2;
}


int main(){
    int n = 1;
   //cin >> n;
    while(n){
        n--;
        solution();
    }
}

Submission Info

Judge Result