uva140-带宽

#include<stdio.h>
#include<stdlib.h> 
#include<string.h>
#include<algorithm>
using namespace std;
#define MAX_LEN 200
char P[MAX_LEN], A[MAX_LEN];
char Final[MAX_LEN];
bool used[MAX_LEN];
bool G[MAX_LEN][MAX_LEN];
int n, minval;
bool ex(char cha)
{
    for(int i=0; i<n; i++) if(P[i]==cha) return true;
    return false;
}
void Read()
{
    char c;
    c = getchar();
    while(c != ‘\n‘) {
        if(!ex(c)) P[n++] = c; getchar();
        char root = c;
        while((c=getchar()) != ‘;‘&&c!=‘\n‘) {
            if(c == ‘ ‘) continue;
            else { if(!ex(c)) P[n++] = c;
                G[root][c] = true; G[c][root] = true; }
        }
        if(c!=‘\n‘) c = getchar();
    }
}
int CalWid(int dex)
{
    int value = 0;
    for(int i=0; i<dex-1; i++) {
        for(int j=i+1; j<dex; j++) if(G[A[i]][A[j]]) {
            if(abs(i-j)>value) value = abs(i-j);
        }
    }
    return value;
}
void Search(int cur)
{
    if(CalWid(cur) >= minval) return ;
    if(cur == n) { int wid=CalWid(cur); if(wid<minval) minval=wid; 
        for(int i=0; i<cur; i++) Final[i] = A[i]; return ; }
    for(int i=0; i<n; i++) if(!used[P[i]]) {
        A[cur] = P[i];
        used[P[i]] = true;
        Search(cur+1);
        used[P[i]] = false;
    }
}
int main()
{
    char ch;
    ch = getchar();
    while(ch != ‘#‘) {
        ungetc(ch, stdin);
        memset(used, 0, sizeof(used));
        memset(G, 0, sizeof(G));
        minval = 1000; n = 0;
        Read();
        sort(P, P+strlen(P));
        Search(0);
        for(int i=0; i<n; i++) printf("%c ", Final[i]);
        printf("-> %d\n", minval);
        ch = getchar();
    }
    return 0;
}