hdu 1195

// Accepted 1195 78MS 364K 2126 B C++ robotcator #include <cstdio>#include <cstring>#include <iostream>#include <queue>using namespace std;const int maxn = 11000+50;struct password{  char data[5];  int step;};password s, e;int vis[maxn];int get_key(password x){  int sum = 0;  for(int i = 0; i < 4; i ++)    sum = sum*10 + x.data[i]-'0';  return sum;}void bfs(){  memset(vis, 0, sizeof(vis));  queue<password> q;  s.step = 0;  q.push(s);  vis[get_key(s)] = 1;  password cur, next;  while(!q.empty()){      cur = q.front();      q.pop();      if(strcmp(cur.data, e.data) == 0){        printf("%d\n", cur.step);        return ;      }      for(int i = 0; i < 3; i ++){          if(i == 0){ // 任意位上加1            for(int j = 0; j < 4; j ++){              strcpy(next.data, cur.data);              next.data[j] = (next.data[j]-'0'+1) == 10 ? 1+'0' : next.data[j]+1;              // 复制粘贴一定要注意代码间的区别              if(vis[get_key(next)] == 0) {                next.step = cur.step + 1;                q.push(next);                vis[get_key(next)] = 1;                // 要区分等号和赋值号              }            }          }          else if(i == 1){ // 任意位上减1            for(int j = 0; j < 4; j ++){              strcpy(next.data, cur.data);              next.data[j] = (next.data[j]-'0'-1) == 0 ? 9+'0' : next.data[j]-1;              if(vis[get_key(next)] == 0) {                next.step = cur.step + 1;                q.push(next);                vis[get_key(next)] = 1;              }            }          }          else if(i == 2){ // 交换            for(int j = 0; j < 3; j ++){              strcpy(next.data, cur.data);              next.data[j] = cur.data[j+1];              next.data[j+1] = cur.data[j];              if(vis[get_key(next)] == 0) {                next.step = cur.step + 1;                q.push(next);                vis[get_key(next)] = 1;              }            }          }      }  }}int main(){  int t;  scanf("%d", &t);  while(t--){    scanf("%s %s", s.data, e.data);    bfs();  }  return 0;}