曼哈顿距离：|x1 - x2| + |y1 - y2|
欧几里德距离: fabs((x1 - x2) + (y1-  y2))
#include <iostream>
#include <cstring>
#include <cstdio>
#include <algorithm>
#include <cmath>
using namespace std;
const int N = 1e4 + 10;
int m,n,w;

int main(){
    scanf("%d%d%d",&w,&m,&n);
    m--,n--;
    int x1 = m / w,x2 = n / w;
    int y1 = m % w,y2 = n % w;
    if(!(x1 & 1))  y1 = w - 1 - y1;
    if(!(x2 & 1))  y2 = w - 1 - y2;
    printf("%d\n",abs(x1 - x2) + abs(y1 - y2));
    return 0;
}