http://codeforces.com/contest/1117/problem/C
题意:给定起终点,n个风向(循环),顺风则移动2步,成角度则到角度的一步,逆风不动;问是否能到达终点;
思路:相当于先随风移动再自由移动,二分天数k,看到k天后在哪个位置,然后自由移动能不能到终点;
#include<algorithm>
#include<set>
#include<vector>
#include<queue>
#include<cmath>
#include<cstring>
#include<iostream>
#include<algorithm>
#include<set>
#include<vector>
#include<queue>
#include<cmath>
#include<cstring>
#include<sstream>
#include<cstdio>
#include<ctime>
#include<map>
#include<stack>
#include<string>
using namespace std;
#define sfi(i) scanf("%d",&i)
#define pri(i) printf("%d\n",i)
#define sff(i) scanf("%lf",&i)
#define ll long long
#define mem(x,y) memset(x,y,sizeof(x))
#define INF 0x3f3f3f3f
#define eps 1e-6
#define PI acos(-1)
#define lowbit(x) ((x)&(-x))
#define zero(x) (((x)>0?(x):-(x))<eps)
#define fl() printf("flag\n")
ll gcd(ll a,ll b){while(b^=a^=b^=a%=b);return a;}
const int maxn=2e5+9;
const int mod=1e9+7;
template <class T>
inline void sc(T &ret)
{
char c;
ret = 0;
while ((c = getchar()) < '0' || c > '9');
while (c >= '0' && c <= '9')
{
ret = ret * 10 + (c - '0'), c = getchar();
}
}
char s[maxn];
ll dx[maxn],dy[maxn];
ll n;
ll sx,sy,ex,ey;
bool ch(ll mid)
{
ll nx=(mid/n)*dx[n]+dx[mid%n];
ll ny=(mid/n)*dy[n]+dy[mid%n];
if( abs(sx-ex+nx)+abs(sy-ey+ny) <=mid ) return 1;
return 0;
}
int main()
{
cin>>sx>>sy>>ex>>ey;
cin>>n;
scanf("%s",s+1);
for(int i=1;i<=n;i++)
{
dx[i]=dx[i-1];
dy[i]=dy[i-1];
if(s[i]=='U') dy[i]++;
if(s[i]=='D') dy[i]--;
if(s[i]=='L') dx[i]--;
if(s[i]=='R') dx[i]++;
}
ll l=0;
ll ans=-1;
ll r=1e18;
while(l<=r)
{
ll mid=(l+r)>>1;
if(ch(mid))
{
ans=mid;
r=mid-1;
}
else l=mid+1;
}
cout<<ans<<endl;
return 0;
}