L. The Heaviest Non-decreasing Subsequence Problem -最長不降子序列變形nlogn-2017 ACM-ICPC 亞洲區(南寧賽區)網絡賽

Let SSS be a sequence of integers s1s_{1}s1,s2s_{2}s2,.........,sns_{n}sn Each integer is is associated with a weight by the following rules:

(1) If is is negative, then its weight is 000.

(2) If is is greater than or equal to 100001000010000, then its weight is 555. Furthermore, the real integer value of sis_{i}si is si−10000s_{i}-10000si10000 . For example, if sis_{i}si is 101011010110101, then is is reset to 101101101 and its weight is 555.

(3) Otherwise, its weight is 111.

A non-decreasing subsequence of SSS is a subsequence si1s_{i1}si1,si2s_{i2}si2,.........,siks_{ik}sik, with i1<i2 ... <iki_{1}<i_{2}\ ...\ <i_{k}i1<i2 ... <ik, such that, for all 1≤j<k1 \leq j<k1j<k, we have sij<sij+1s_{ij}<s_{ij+1}sij<sij+1.

A heaviest non-decreasing subsequence of SSS is a non-decreasing subsequence with the maximum sum of weights.

Write a program that reads a sequence of integers, and outputs the weight of its

heaviest non-decreasing subsequence. For example, given the following sequence:

808080757575737373939393737373737373101011010110101979797−1-11−1-11114114114−1-11101131011310113118118118

The heaviest non-decreasing subsequence of the sequence is <73,73,73,101,113,118><73, 73, 73, 101, 113, 118><73,73,73,101,113,118> with the total weight being 1+1+1+5+5+1=141+1+1+5+5+1 = 141+1+1+5+5+1=14. Therefore, your program should output 141414 in this example.

We guarantee that the length of the sequence does not exceed 2∗1052*10^{5}2105

Input Format

A list of integers separated by blanks:s1s_{1}s1,s2s_{2}s2,.........,sns_{n}sn

Output Format

A positive integer that is the weight of the heaviest non-decreasing subsequence.

樣例輸入

80 75 73 93 73 73 10101 97 -1 -1 114 -1 10113 118

樣例輸出

14


/*
題意:
給你一個數列,當該數數值<0時該數無價值,
當該數數值>=10000時 該數值-=10000,其價值爲5,
其餘情況價值爲1
問價值和最大的非降子序列是多少

題解:
價值可以轉換爲長度
>=10000的數,就在數組中存5次
<0的數因爲沒價值,並且求得是子序列不是子串,不影響最後序列的選取,所以根本不用存
最後求得的長度即爲答案
*/

#include <bits/stdc++.h>
#include <cstdio>

using namespace std;

int a[1000010];
int f[1000010];
int d[1000010];

int _bsearch(const int *f, int len, const int &a)
{
    int l = 0, r = len - 1;
    while(l <= r)
    {
        int mid = (l + r) / 2;
        if(a >= f[mid - 1]  && a < f[mid])
            return mid;
        else if(a < f[mid])
            r = mid - 1;
        else
            l = mid + 1;
    }
}

int LIS(const int *a, const int &n)
{
    int i,j,len = 1;
    f[0] = a[0];
    d[0] = 1;
    for(i = 1; i < n; i++)
    {
        if(a[i] < f[0])
            j = 0;
        else if(a[i] >= f[len - 1])
            j = len++;
        else
            j = _bsearch(f, len, a[i]);
        f[j] = a[i];
        d[i] = j + 1;
    }

    return len;
}

int main()
{
    int temp;
    int len = 0;

    while(cin>>temp)
    {
        if(temp > 0 && temp < 10000)
        {
            a[len++] = temp;
        }
        else if(temp >= 10000)
        {
            for(int i = 0; i < 5; i++)
                a[len++] = temp - 10000;
        }
    }
    int ans = LIS(a,len);
    cout<<ans<<endl;

    return 0;
}




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