#include <bits/stdc++.h>
using namespace std;
int main() {
int n;
int xCo [n];
int ID [n];
cin >> n;
for (int i=0;i<n;i++) {
if (i%2 == 0) {
cin>>xCo[i-1];
}else {
cin>>ID[i-1];
}
}
}
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