LeetCode Word Ladder

 //小的能过，大的内存超限，故大于3000则不处理  :)
 1 char edge[3000][3000]={0};
 2 int  len[3000]={0};
 3 
 4 class Solution {
 5 public:
 6     
 7     int countL;
 8     int findShort()
 9     {
10         int i,j,k;
11         len[0]=0;
12         vector<int> q,qq;
13         q.push_back(0);
14         for( ;q.size(); )
15         {
16             for(j=0;j<q.size();j++)
17             {
18                 int ttt=q[j];
19                 for(k=0;k<countL;k++)
20                 {
21                     if(edge[ttt][k])
22                     {
23                         if(len[ttt]!=-1&&len[k]==-1)
24                         {
25                                 len[k]=len[ttt]+1;
26                                 qq.push_back(k);
27                         }
28                     }
29                 }
30             }
31             q=qq;
32             qq.clear();
33         }
34         return len[1];
35     }
36     void initLen()
37     {
38         int i;
39         for(i=0;i<countL;i++)
40             len[i]=-1;
41     }
42     bool cal(string &s1,string &s2)
43     {
44         const char*p=s1.c_str();
45         const char*q=s2.c_str();
46         int i=0;
47         int c=0;
48         for(;p[i];i++)
49         {
50             if(p[i]!=q[i])
51                 c++;
52         }
53         if(c==1)
54             return true;
55         return false;
56     }
57     void calMatrix(vector<string> &v)
58     {
59         int i,j;
60         for(i=0;i<v.size();i++)
61         {
62             for(j=0;j<v.size();j++)
63             {
64                 if(cal(v[i],v[j]))
65                     edge[i][j]=1;
66             }
67         }      
68     }
69     int ladderLength(string start, string end, unordered_set<string> &dict) {
70         // Start typing your C/C++ solution below
71         // DO NOT write int main() function
72         memset(edge,0,9000000);
73         vector<string> v;
74         unordered_set<string> ::iterator p;
75         v.push_back(start);
76         v.push_back(end);
77         for(p=dict.begin();p!=dict.end();p++)
78         {
79             v.push_back(*p);
80         }
81       
82         countL=v.size();
83         if(countL>2000)
84             return 1000;
85         calMatrix(v);
86         initLen();
87         int len2=findShort();
88         if(len2!=-1)
89             return len2+1;
90         return 0;
91     }
92 };