uva140 - Bandwidth

#include<cstdio>
#include<cstring>
#include<vector>
#include<string>
#include<algorithm>
using namespace std;
const int maxn=10;
int id[256], letter[maxn];
int n;

void map_id_letter(char *p) 
{
    n=0;
    for(int c=‘A‘; c<=‘Z‘; c++) if(strchr(p, c)) 
    {
        id[c]=n;
        letter[n]=c;
        n++;
    }
}

int main()
{
    char buff[256];
    while(gets(buff) && buff[0]!=‘#‘)
    {
        map_id_letter(buff);
        char*p=strtok(buff, ";");
        vector<int> u,v;
        while(p)
        {
            //printf("%s\n", p);
            int t=p[0];
            ++p;//跳过:
            while(*(++p))
            {
                u.push_back(id[t]);
                v.push_back(id[*p]);
            }
            p=strtok(0, ";");
        }

        int ans=n;
        int P[maxn], bestP[maxn], pos[maxn];
        for(int i=0;i<n;i++) P[i]=i;
        do
        {
            for(int i=0;i<n;i++) pos[P[i]]=i;
            int bandwidth=0;
            for(int i=0;i<u.size();i++)
            {
                bandwidth=max(bandwidth, abs(pos[u[i]] - pos[v[i]]));
            }
            if(bandwidth<ans)
            {
                ans=bandwidth;
                memcpy(bestP, P, sizeof(P));
            }
        }while(next_permutation(P, P+n));

        for(int i=0;i<n;i++)
        {
            printf("%c ", letter[bestP[i]]);
        }
        printf("-> %d\n", ans);
    }
    
    return 0;
}