#include<iostream>
int main()
{
    int w,m,n;
    std::cin>>w>>m>>n;
    if(n>m)std::swap(n,m);
    int kx,ky,x=0,y=1;
    for(int i=1;i<=m;i+=1)
    {
        if(y%2==1)
        {
            x+=1;
            if(x>w)x=w,y+=1;
        }
        else
        {
            x-=1;
            if(x<1)x=1,y+=1;
        }
        if(i==n)kx=x,ky=y;
    }
    std::cout<<abs(kx-x)+abs(ky-y);
}

这题测试数据不完全；错的代码能AC

#include<bits/stdc++.h>
using namespace std;
int w;

int main(){
	int n,m,r1,c1,r2,c2;
	cin>>w>>n>>m;
	r1=ceil(n*1.0/w);
	if(r1%2==0){
		c1=(w-n%w+1)%w;
	}
	else{
		c1=(n%w==0?w:n%w);
	}
	r2=ceil(m*1.0/w);
	if(r2%2==0){
		c2=(w-m%w+1)%w;
	}
	else{
		c2=(m%w==0?w:m%w);
	}
	//cout<<r1<<" "<<c1<<endl;
    //cout<<r2<<" "<<c2<<endl;
	cout<<abs(r1-r2)+abs(c1-c2);
	return 0;
}

#include<iostream>
int main()
{
    int w,m,n;
    std::cin>>w>>m>>n;
    if(n>m)std::swap(n,m);
    int kx,ky,x=0,y=1;
    for(int i=1;i<=m;i+=1)
    {
        if(y%2==1)
        {
            x+=1;
            if(x>w)x=w,y+=1;
        }
        else
        {
            x-=1;
            if(x<1)x=1,y+=1;
        }
        if(i==n)kx=x,ky=y;
    }
    std::cout<<abs(kx-x)+abs(ky-y);
}

数学解法,@同为数学课代表的应该能看懂吧

(不会有人用for吧)

#include <bits/stdc++.h>
using namespace std;
int main(){
    int w,m,n; cin>>w>>m>>n;
    int mx=m%w,my=ceil(m*1.0/w),
        nx=n%w,ny=ceil(n*1.0/w);
    if(my%2==0)mx=w-mx+1;
    if(ny%2==0)nx=w-nx+1;
    cout<<abs(mx-nx)+abs(my-ny);
    return 0;}