Problem F Free Weights

#include<bits/stdc++.h>
using namespace std;
const int N=1E6+7;
int arr[N];
int brr[N];
int crr[N];
bool mark[N],mark1[N];
const int INF=1e9+7;
const int mm=1e9;
int n;

bool judge(int x){ 
    memset(mark,0,sizeof(mark));
    memset(mark1,0,sizeof(mark1));
    
    for(int i=1;i<=n;i++) {
        if(arr[i]<=x) mark[i]=1;
        if(brr[i]<=x) mark1[i]=1;
    }
    
    
    int pos=0;
    for(int i=1;i<=n;i++){
        if(mark[i]==0) crr[++pos]=arr[i]; 
    }
    
    
    if(pos&1) return 0;
    for(int i=1;i<=pos;i+=2){
        if(crr[i]!=crr[i+1]) return 0;
    }
    pos=0;
    for(int i=1;i<=n;i++){
        if(mark1[i]==0) crr[++pos]=brr[i];
    }
    if(pos&1) return 0;
    for(int i=1;i<=pos;i+=2) {
        if(crr[i]!=crr[i+1]) return 0;
    }
    return 1;
}

void solve(){
    cin>>n;
    for(int i=1;i<=n;i++) scanf("%d",&arr[i]);
    for(int j=1;j<=n;j++) scanf("%d",&brr[j]);
    int l=0,r=mm;
    int ans=INF;
    while(l<=r){
        int mid=(l+r)/2;
        if(judge(mid)){
            r=mid-1;
            ans=min(ans,mid);
        }
        else l=mid+1;
    }
    
    cout<<ans<<endl;
}

int main(){
    solve();
    return 0;
}