1poj 3278

#include
    
     #include
     
      #include
      
       #include
       
        #include
        
         #include
         
          using namespace std;#define N 100005#define M 155#define INF 0x3f3f3f3fstruct node{ int x, t;}st;int n, k, a, b, x, y, t, cnt, ans;bool v[N];void Bfs(int n){ ans = 0; queue
          
           q; while(!q.empty()) q.pop(); memset(v, 0, sizeof(v)); st.x = n; st.t = 0; q.push(st); v[st.x] = 1; while(!q.empty()) { node head = q.front(); q.pop(); if(head.x == k) { ans = head.t; return; } for(int i = 0; i < 3; i++) { node next = head; if(i == 0) next.x = head.x + 1; else if(i == 1) next.x = head.x - 1; else next.x = head.x * 2; next.t = head.t + 1; if(next.x < 0 || next.x > 100000) continue; if(v[next.x] == 1 ) continue; // 一开始写成一行，if(v[next.x] == 1 || next.x < 0 || next.x > 100000) continue; 找了好久的bug，以后能分开的还是分开吧，不要省那一两行 q.push(next); v[next.x] = 1; } }}int main(){ while(cin>>n>>k){ Bfs(n); cout<
           
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