OJ-Problems-Source/HDOJ/4963_autoAC.cpp
2016-09-10 11:34:41 +08:00

137 lines
2.9 KiB
C++

#include <cstdio>
#include <cstring>
#include <cmath>
#include <cstdlib>
#include <iostream>
#include <algorithm>
#include <queue>
#include <map>
#include <set>
#include <vector>
#include <cctype>
using namespace std;
const int maxn=44;
const int maxm=(1<<20)+10;
const int INF=1e9;
char a[maxn];
int c[maxn],b[maxn],x,y,xx,yy,sx,sy,t,f[maxn],g[maxm],len[maxn];
struct node{
int id,w,flag;
bool operator <(const node &a)const{
if(id==a.id)return w<a.w;
return id<a.id;
}
}e[maxm*2];
int bitcount(int i)
{
int x=0;
while(i)
{
x+=(i&1);
i=i>>1;
}
return x;
}
void init()
{
for(int i=0;i<=22;i++)
{
f[i]=(1<<i)-1;
len[i]=i*10000000;
}
for(int i=0;i<(1<<20);i++)
{
g[i]=bitcount(i);
}
}
void judge()
{
int i,j,k;
if((y>>(yy-xx))^x)return ;
e[t].flag=0;
e[t].id=len[yy-xx]+(y&f[yy-xx]);
e[t++].w=sy-sx;
}
void judge2()
{
int i,j,k,p;
if(x^(y&f[xx]))return ;
e[t].flag=1;
e[t].id=len[yy-xx]+(y>>xx);
e[t++].w=sy-sx;
}
int main()
{
init();
int n;
while(scanf("%d",&n)!=EOF)
{
if(n==0)break;
int i,j,k=0,ans=INF;
scanf("%s",a);
for(i=0;i<2*n;i++)
{
b[i]=a[i]-'a';
k+=b[i];
}
for(i=0;i<n*2;i++)
scanf("%d",&c[i]);
if(k%2){printf("-1\n");continue;}
t=0;
for(i=0;i<(1<<n);i++)
{
if(g[i]>n-g[i])continue;
x=y=xx=yy=sx=sy=0;
for(j=n-1;j>=0;j--)
{
if((1<<j)&i)
{
x=(x<<1)|b[n-1-j];
sx+=c[n-1-j];
xx++;
}
else
{
y=(y<<1)|b[n-1-j];
sy+=c[n-1-j];
yy++;
}
}
if(xx<=yy)judge();
}
for(i=0;i<(1<<n);i++)
{
if(g[i]>n-g[i])continue;
x=y=xx=yy=sx=sy=0;
for(j=n-1;j>=0;j--)
{
if((1<<j)&i)
{
x=(x<<1)|b[2*n-1-j];
sx+=c[2*n-1-j];
xx++;
}
else
{
y=(y<<1)|b[2*n-1-j];
sy+=c[2*n-1-j];
yy++;
}
}
if(xx<=yy)judge2();
}
sort(e,e+t);
int p=-1,q=-1;
for(i=0;i<t;i++)
{
if(e[i].flag==0)p=i;
else q=i;
if(p==-1||q==-1)continue;
if(e[p].id==e[q].id)ans=min(ans,abs(e[p].w-e[q].w));
}
if(ans==INF)printf("-1\n");
else printf("%d\n",ans);
}
return 0;
}