Submission #1841309

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Source Code Expand

#include <iostream>
#include <cstdio>
#include <cstring>
#include <algorithm>

using namespace std;

const int MAXN = 1e5 + 10;
int a[MAXN] , b[MAXN];
int la = 0 , lb = 0;
int n;
int main(){
	ios::sync_with_stdio(0);
	cin >> n;
	for(int i = 1 ; i <= n ; ++ i){
		int x;
		cin >> x;
		if(i & 1) a[++ la] = x;
		else b[++ lb] = x;
	}
	sort(a + 1 , a + la + 1);
	sort(b + 1 , b + lb + 1);
	int ans = 0 , now = 0 , sa = 1 , sb = 1;
	while(sa <= la && sb <= lb){
		++ now;
		if(a[sa] < b[sb]){
			if(!(now & 1)) ans ++;
			sa ++;
		}
		else
			sb ++;
	}
	while(sa <= la){
		++ now;
		if(!(now & 1)) ans ++;
		sa ++;
	}
	cout << ans << endl;
	return 0;
}

Submission Info

Judge Result