Vasya and Book
阿新 • • 發佈:2018-11-30
https://codeforces.com/contest/1082/problem/A
題解:
一共四種情況
1、往左走沒有到n就達到目的地(包括目的地為n)
2、往右走沒有到1就達到目的地(包括目的地為1)
3、往左走到n,回頭再達到目的地
4、往右走到1,回頭再達到目的地
/* *@Author: STZG *@Language: C++ */ #include <bits/stdc++.h> #include<iostream> #include<algorithm> #include<cstdlib> #include<cstring> #include<cstdio> #include<string> #include<vector> #include<bitset> #include<queue> #include<deque> #include<stack> #include<cmath> #include<list> #include<map> #include<set> //#define DEBUG using namespace std; typedef long long ll; const int N=10000; const double PI = acos(-1.0); const double EXP = 1E-8; const ll INF = 0x3f3f3f3f3f3f3f; int t; ll n,x,y,d,m; int main() { #ifdef DEBUG freopen("input.in", "r", stdin); //freopen("output.out", "w", stdout); #endif scanf("%d",&t); while(t--){ scanf("%I64d%I64d%I64d%I64d",&n,&x,&y,&d); if(labs(x-y)%d==0){ cout << labs(x-y)/d << endl; }else{ int l=(x-1)/d; if((x-1)%d)l++; int r=(n-x)/d; if((n-x)%d)r++; ll ans=INF; if((y-1)%d==0){ ans=min(ans,l+(y-1)/d); } if((n-y)%d==0){ ans=min(ans,r+(n-y)/d); } if(ans!=INF){ cout << ans << endl; }else{ cout << -1 << endl; } } } //cout << "Hello world!" << endl; return 0; }