!DO NOT READ!... this solution is way too easy

#1 
#include<bits/stdc++.h>
#define rep(i,a,b)       for(long long int i=a;i<b;i++)
#define input(a,n)       for(long long int i=0;i<n;i++)cin>>a[i];
#define set(a,n, x)      for(long long int i=0;i<n;i++)a[i]=x;
#define dikhao(a,n)      for(long long int i=0;i<n;i++)cout<<a[i]<<" ";cout<<endl;
#define ll              long long int
#define mp              make_pair
#define pb              push_back
#define all(a) a.begin(),a.end()
#define mx(a) *max_element(all(a))
#define mn(a) *min_element(all(a))
using namespace std;
int maxsize = 200001;
double power(float x, int y)  
{  
    float temp;  
    if(y == 0)  
        return 1;  
    temp = power(x, y / 2);  
    if (y % 2 == 0)  
        return temp * temp;  
    else
    {  
        if(y > 0)  
            return x * temp * temp;  
        else
            return (temp * temp) / x;  
    }  
}  

bool valid(int i,int j,int A,int B){
    if(i>=1 && i<=A && j>=1 && j<=B)return true;
    return false;
}

int mins[501][501];
int solve(int A, int B, int C, int D, int E, int F) {
    for(int i= 0; i<=A; i++){
        for(int j=0; j<=B; j++){
            mins[i][j] = INT_MAX;
        }
    }
    mins[C][D] = 0;
    int movesx[] = {1,2,-1,2,-1,-2,1,-2};
    int movesy[] = {2,1,2,-1,-2,-1,-2,1};
    queue<pair<int, int> > q;
    q.push(make_pair(C, D));
    pair<int, int> cur ;
    while(!q.empty()){
        cur = q.front();
        q.pop();
        int x, y;
        for(int i =0; i<8; i++){
            x = cur.first+ movesx[i];
            y = cur.second+ movesy[i];   
            if(valid(x, y, A, B) && mins[x][y] == INT_MAX){
            // cout<<x<<' '<<y<<endl; 
                mins[x][y] = min( mins[x][y], 1+ mins[cur.first][cur.second]);
                q.push(make_pair(x, y));
            }
        }
    }
    // for(int i= 1    ; i<=A; i++){
    //     for(int j=1; j<=B; j++){
    //         cout<<mins[i][j]<<" ";
    //     }
    //     cout<<endl;
    // }
    return mins[E][F];
}


int main(){
    cout<<solve(4,4,1,1,4,4)<<endl;
    return 0;
}