uva 140 Bandwidth(全排列+递归)

快睡觉的时候1A的

把序列全排列，递归暴力判断就ok啦，我改成对应的整数存了，a数组存的是所有的字符的排列，

b数组存的是所有开始节点的排列，map[i][j]数组存的是i为起点，与j相邻

贴代码：

#include<stdio.h>
#include<stdlib.h>
#include<string.h>
#include<limits.h>
#include<math.h>
#include<algorithm>
using namespace std;
int map[10][30];
int a[30];
int b[10];
int visit[30];
int Min,s,Max2;
int ma[30];
int cmp(const void *c,const void *d)
{
return *(int *)c - *(int *)d;
}
void dfs(int x,int y)
{
int Max1 = 0;
for(int i=0; i<s; i++)
{
if(map[x][a[i]] == 1)
{
if(abs(y-i) > Max1)
Max1 = abs(y-i);
}
}
if(Max1 > Max2)
Max2 = Max1;
return ;
}
int main()
{
char ch;
int i,j,flag = 1,k=0;
s = 0;
Min = INT_MAX;
memset(a,0,sizeof(a));
memset(b,0,sizeof(b));
memset(visit,0,sizeof(visit));
memset(map,0,sizeof(map));
while(scanf("%c",&ch),ch!='#')
{
if(ch >= 'A' && ch <= 'Z' && (visit[ch-'A'] == 0))
{
visit[ch - 'A'] = 1;
a[s++] = ch - 'A';
}
if(ch >= 'A' && ch <= 'Z' && (flag == 1))
{
i = ch - 'A';
b[k++] = i;
}
else if(ch >= 'A' && ch <= 'Z' && (flag == 0))
map[i][ch-'A'] = 1;
else if(ch == ':')
flag = 0;
else if(ch == ';')
{
flag = 1;
continue;
}
else if(ch == '\n')
{
qsort(a,s,sizeof(a[0]),cmp);
do
{
Max2 = 0;
for(i=0; i<s; i++)
{
for(j=0; j<k; j++)
{
if(a[i] == b[j])
dfs(a[i],i);
}
}
if(Max2 < Min)
{
Min = Max2;
for(int p=0; p<s; p++)
{
ma[p] = a[p];
}
}
}while(next_permutation(a,a+s));
for(i=0; i<s; i++)
printf("%c ",ma[i]+'A');
printf("-> ");
printf("%d\n",Min);
memset(a,0,sizeof(a));
memset(b,0,sizeof(b));
memset(visit,0,sizeof(visit));
memset(map,0,sizeof(map));
s = k = 0;
flag = 1;
Min = INT_MAX;
}

}
return 0;
}