481 - What Goes Up

需要用到NlogN的LIS

  1 #include <cstdio>
  2 #include <iostream>
  3 #include <cstring>
  4 #include <vector>
  5 #include <algorithm>
  6 
  7 using namespace std;
  8 
  9 int f[65535];
 10 int from[65535];
 11 vector<int> row;
 12 int flag1,flag2;
 13 int temp[65535];
 14 int ans = 0;
 15 vector<int> v;
 16 
 17 int max(int a,int b)
 18 {
 19     return a>b?a:b;
 20 }
 21 
 22 //const int N = 1001;
 23 // f[i]用于记录a[0...i]的最大长度
 24 /*
 25 int bsearch(const int *C, int size, const int &a)
 26 
 27 {
 28 
 29     int l=0, r=size-1;
 30 
 31     while( l <= r )
 32 
 33     {
 34 
 35         int mid = (l+r)/2;
 36 
 37         if( a > C[mid-1] && a < C[mid] ) return mid; // >&&<= 换为: >= && <
 38 
 39         else if( a < C[mid] ) r = mid-1;
 40 
 41         else l = mid+1;
 42 
 43     }
 44 
 45 }
 46 
 47 int C[65535];
 48 
 49 int LIS(const int *a, const int &n){
 50 
 51      int i, j, size = 1;
 52 
 53      C[0] = a[0]; f[0] = 1;
 54 
 55      for( i=1; i < n; ++i ){
 56 
 57           if( a[i] < C[0] ) j = 0;                 // <= 换为: <
 58 
 59          else if( a[i] >= C[size-1] ) j = size++;   // > 换为: >=
 60 
 61          else j = bsearch(C, size, a[i]);
 62 
 63          C[j] = a[i]; f[i] = j+1;
 64      }
 65 
 66      return size;
 67 
 68 }
 69 */
 70 
 71 int bsearch(int &a)
 72 {
 73     int l = 0;
 74     int r = v.size()-1;
 75     int m;
 76     while(l<=r)
 77     {
 78         m = (l+r)/2;
 79         if (v[m]<a) l= m+1;
 80         else r=m-1;
 81     }
 82     v[l] = a;
 83     return l;
 84 }
 85 
 86 int LIS(vector<int>& s)
 87 {
 88     if (s.size() == 0) return 0;
 89 
 90     v.push_back(s[0]);
 91 
 92     f[0] = 1;
 93 
 94     for (int i = 1; i < s.size(); ++i)
 95     {
 96         int n = s[i];
 97 
 98         if (n > v.back())
 99         {
100             v.push_back(n);
101             f[i] = v.size();
102         }
103         else
104         {
105             f[i] = bsearch(n)+1;
106         }
107     }
108     return v.size();
109 }
110 int main()
111 {
112     //freopen("ex.in","r",stdin);
113     int len=0;
114     int temps;
115     for(; cin>>temps;)
116     {
117 
118         row.push_back(temps);
119         len++;
120     }
121     ans = LIS(row);
122     flag1 = ans;
123     vector<int> lis;
124     for (int i = row.size()-1;i>=0;i--)
125         {
126             if (f[i] == flag1)
127                 {
128                     flag1--;
129                     lis.push_back(row[i]);
130                 }
131             if (flag1 == 0)
132                 break;
133         }
134     cout<<ans<<endl<<"-"<<endl;
135     for (int i=lis.size()-1;i>=0;i--)
136         cout<<lis[i]<<endl;
137     return 0;
138 }

posted on 2011-08-02 19:39  cherryunix  阅读(197)  评论(0)    收藏  举报

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