B - Second My Problem First HDU -单调队列

• B - Second My Problem First

•  HDU - 3706
• 单调队列维护固定长度的区间的最小值即可。 

• #include<bits/stdc++.h>
  using namespace std;
  #define maxn 11111111
  #define ll long long
  int L, n,a,b;
  ll ans,num;
  deque<pair<int,ll> >minn;
  int main()
  {
      while(~scanf("%d%d%d",&n,&a,&b))
      {
          ans=num=1;
          while(!minn.empty())
              minn.pop_back();
          for(int i=1; i<=n; i++)
          {
              L=max(1,i-a);
              num=(num*a)%b;
              while(!minn.empty()&&num<minn.back().second)
                  minn.pop_back();
              minn.push_back(make_pair(i,num));
              while(!minn.empty()&&L>minn.front().first)
                  minn.pop_front();
              ans=ans*minn.front().second%b;
          }
          printf("%lld\n",ans);
      }
      return 0;
  }