HDU 4604 Deque(最长上升子序)

题目链接

本来就对N*log(N)算法不大会....然后各种跪了，求出最长不下降+最长不上升-最少相同元素。求相同元素，用二分求上界搞的。代码里4个二分....

  1 #include <cstdio>

  2 #include <cstring>

  3 #include <iostream>

  4 #include <cmath>

  5 #include <algorithm>

  6 using namespace std;

  7 int d[200001];

  8 int dd[200001];

  9 int f[200001];

 10 int a[200001];

 11 int same[200001];

 12 int n;

 13 int bin1(int size,int x)

 14 {

 15     int l = 0,r = size-1,mid;

 16     while(l <= r)

 17     {

 18          mid = (l+r)/2;

 19         if(x >= f[mid-1]&&x < f[mid])

 20         return mid;

 21         else if(x < f[mid]) r = mid-1;

 22         else l = mid + 1;

 23     }

 24     return mid;

 25 }

 26 int binx(int size,int x)

 27 {

 28     int str = 0,end = size-1,mid;

 29     while(str < end)

 30     {

 31         mid = (str+end)/2;

 32         if(f[mid] < x)

 33         str = mid + 1;

 34         else

 35         end = mid;

 36     }

 37     return str;

 38 }

 39 void LIS1()

 40 {

 41     int i,j,size = 1,k;

 42     f[0] = a[0];d[0] = 1;

 43     same[0] = 1;

 44     for(i = 1;i < n;i ++)

 45     {

 46         if(a[i] < f[0])

 47         {

 48             j = 0;

 49             k = 0;

 50         }

 51         else if(a[i] >= f[size-1])

 52         {

 53             j = size ++;

 54             k = binx(size,a[i]);

 55         }

 56         else

 57         {

 58             j = bin1(size,a[i]);

 59             k = binx(size,a[i]);

 60         }

 61         f[j] = a[i];d[i] = j + 1;

 62         same[i] = min(same[i],j-k+1);

 63     }

 64 }

 65 int bin2(int size,int x)

 66 {

 67     int l = 0,r = size-1,mid;

 68     while(l <= r)

 69     {

 70         mid = (l+r)/2;

 71         if(x <= f[mid-1]&&x > f[mid])

 72         return mid;

 73         else if(x > f[mid]) r = mid-1;

 74         else l = mid + 1;

 75     }

 76     return mid;

 77 }

 78 int bins(int size,int x)

 79 {

 80     int str = 0,end = size-1,mid;

 81     while(str < end)

 82     {

 83         mid = (str+end)/2;

 84         if(f[mid] > x)

 85         str = mid + 1;

 86         else

 87         end = mid;

 88     }

 89     return str;

 90 }

 91 void LIS2()

 92 {

 93     int i,j,size = 1,k;

 94     f[0] = a[0];d[0] = 1;

 95     same[0] = 1;

 96     for(i = 1;i < n;i ++)

 97     {

 98         if(a[i] > f[0])

 99         {

100             j = 0;

101             k = 0;

102         }

103         else if(a[i] <= f[size-1])

104         {

105             j = size ++;

106             k = bins(size,a[i]);

107         }

108         else

109         {

110             j = bin2(size,a[i]);

111             k = bins(size,a[i]);

112         }

113         f[j] = a[i];d[i] = j + 1;

114         same[i] = min(same[i],j - k + 1);

115     }

116 }

117 int main()

118 {

119     int t,i;

120     scanf("%d",&t);

121     while(t--)

122     {

123         scanf("%d",&n);

124         for(i = 0;i < n;i ++)

125         {

126             scanf("%d",&a[i]);

127             same[i] = 1000000;

128         }

129         for(i = 0;i < n/2;i ++)

130         swap(a[i],a[n-i-1]);

131         memset(d,0,sizeof(d));

132         memset(f,0,sizeof(f));

133         LIS1();

134         for(i = 0;i < n;i ++)

135         {

136             dd[i] = d[i];

137         }

138         memset(d,0,sizeof(d));

139         memset(f,0,sizeof(f));

140         LIS2();

141         int maxz = 0;

142         /*for(i = 0;i < n;i ++)

143         {

144             printf("%d ",dd[i]);

145         }

146         printf("\n");

147         for(i = 0;i < n;i ++)

148         {

149             printf("%d ",d[i]);

150         }

151         printf("\n");

152         for(i = 0;i < n;i ++)

153         {

154             printf("%d ",same[i]);

155         }

156         printf("\n");

157         */

158         for(i = 0;i < n;i ++)

159         maxz = max(maxz,dd[i]+d[i]-same[i]);

160         printf("%d\n",maxz);

161     }

162     return 0;

163 }