BbVUDH - Online C++0x Compiler & Debugging Tool

#include<bits/stdc++.h>
using namespace std;
typedef long long ll;
typedef unsigned long long ull;
typedef long double lld;
/*
#include <ext/pb_ds/assoc_container.hpp>
#include <ext/pb_ds/tree_policy.hpp>
using namespace __gnu_pbds;

template<class T> using ordered_set =tree<T, null_type, less<T>, rb_tree_tag,tree_order_statistics_node_update>;
// ordered_set.find_by_order(k) returns the iterator to kth element
// ordered_set.order_of_key(k) returns the number of elements strictly less than k

(FOR ORDERED MULTISET "UPPER_BOUND" AND "LOWER_BOUND" ARE REVERSED)
template<class T> using ordered_multiset =tree<T, null_type, less_equal<T>, rb_tree_tag,tree_order_statistics_node_update>;
// ordered_set.find_by_order(k) returns the iterator to kth element
// ordered_set.order_of_key(k) returns the number of elements strictly less than k
*/
#ifdef LOCALIO
    #define dbg(...) cerr<< __VA_ARGS__;
    #define dbgl(...) cerr<< __VA_ARGS__<<nl;
#else
    #define dbg(...) ;
    #define dbgl(...) ;
#endif
#define fastio ios_base::sync_with_stdio(0); cin.tie(0);
#define all(x) x.begin(),x.end()
#define nl '\n'
#define pb(x) push_back(x)
#define sz(x) (int)x.size()
#define szl(x) (long long)x.size()

// const int mod = 998244353;
const int mod = 1e9+7;


void solve()
{
    int n; cin>>n;
    int a[n],b[n];
    for(auto &i:a) cin>>i;
    for(auto &i:b) cin>>i;

    int pre[n],suf[n];

    pre[0] = 1;
    for(int i=1; i<n; ++i) pre[i] = (b[i]==b[i-1])?pre[i-1]:pre[i-1]+1;
    pre[0] = (a[0]==b[0])?0:1;
    for(int i=1; i<n; ++i) pre[i] = (a[i]==b[i]?pre[i-1]:pre[i]);


    reverse(a,a+n);
    reverse(b,b+n);

    suf[0] = 1;
    for(int i=1; i<n; ++i) suf[i] = (b[i]==b[i-1])?suf[i-1]:suf[i-1]+1;
    suf[0] = (a[0]==b[0])?0:1;
    for(int i=1; i<n; ++i) suf[i] = (a[i]==b[i]?suf[i-1]:suf[i]);

    reverse(suf,suf+n);


    int ans = min(suf[0],pre[n-1]);

    for(int i=1; i<n; ++i)
    {
        ans = min(ans,pre[i-1]+suf[i]);
    }


    cout<<ans<<nl;


}

signed main() {
    fastio;
    #ifdef LOCALIO
        freopen("error.txt", "w", stderr);
    #endif
    int t=1;
    // cin>>t;
    while(t--)
    {
        solve();
    }
}