sts vector from seconds -m OS AS nbsp print

F. Consecutive Subsequence time limit per test 2 seconds memory limit per test 256 megabytes input standard input output standard output

You are given an integer array of length $\mathrm{nn.}$

You have to choose some subsequence of this array of maximum length such that this subsequence forms a increasing sequence of consecutive integers. In other words the required sequence should be equal to $[x,x+1,\dots ,x+k?1][x,x+1,\dots ,x+k?1]\; for\; some\; value\; xx\; and\; length\; kk.$

Subsequence of an array can be obtained by erasing some (possibly zero) elements from the array. You can erase any elements, not necessarily going successively. The remaining elements preserve their order. For example, for the array $[5,3,1,2,4][5,3,1,2,4]\; the\; following\; arrays\; are\; subsequences:\; [3][3],\; [5,3,1,2,4][5,3,1,2,4],\; [5,1,4][5,1,4],\; but\; the\; array\; [1,3][1,3]\; is\; not.$

Input

The first line of the input containing integer number $\mathrm{nn\; (1\le n\le 2?1051\le n\le 2?105)\; —\; the\; length\; of\; the\; array.\; The\; second\; line\; of\; the\; input\; containing\; nn\; integer\; numbers\; a1,a2,\dots ,ana1,a2,\dots ,an\; (1\le ai\le 1091\le ai\le 109)\; —\; the\; array\; itself.}$

Output

On the first line print $\mathrm{kk\; —\; the\; maximum\; length\; of\; the\; subsequence\; of\; the\; given\; array\; that\; forms\; an\; increasing\; sequence\; of\; consecutive\; integers.}$

On the second line print the sequence of the indices of the any maximum length subsequence of the given array that forms an increasing sequence of consecutive integers.

Examples input Copy

7
3 3 4 7 5 6 8

output Copy

4
2 3 5 6 

input Copy

6
1 3 5 2 4 6

output Copy

2
1 4 

input Copy

4
10 9 8 7

output Copy

1
1 

input Copy

9
6 7 8 3 4 5 9 10 11

output Copy

6
1 2 3 7 8 9 

Note

All valid answers for the first example (as sequences of indices):

• $[1,3,5,6][1,3,5,6]$
• $[2,3,5,6][2,3,5,6]$

All valid answers for the second example:

• $[1,4][1,4]$
• $[2,5][2,5]$
• $[3,6][3,6]$

All valid answers for the third example:

• $[1][1]$
• $[2][2]$
• $[3][3]$
• $[4][4]$

All valid answers for the fourth example:

• $[1,2,3,7,8,9]$

題意：給你一個數組找出最長的遞增子序列的長度以及下標位置。

例如第一組樣例：7

3 3 4 7 5 6 8

最長的子序列為3 4 5 6，長度為4。

下標為1 3 5 6或2 3 5 6

題解：用map進行動態規劃，mp[i]表示以i數字開頭的最長的遞增子序列的長度，即有轉移方程mp[i]=max(mp[i],mp[i-1]+1)

最後找出map裏面子序列長度最長的數字i，倒著輸出就行了。

#include<iostream>  
#include<cstdio>  
#include<cstdlib>  
#include<cstring>  
#include<cmath>  
#include<string>  
#include<algorithm>  
#include<vector>  
#include<queue>  
#include<set>  
#include<map>  
#include<stack>  
using namespace std;  
const int inf=0x3f3f3f3f;  
  
  
map<int ,int >dp;  
int t[300005];  
stack<int>s;  
int main()  
{  
    int n;  
    scanf("%d",&n);  
    int ans=-inf;  
    int maxx;  
    for(int i=1;i<=n;i++)  
    {  
        scanf("%d",&t[i]);  
        dp[t[i]]=dp[t[i]-1]+1;  
        if(dp[t[i]]>ans)  
        {  
            ans=dp[t[i]];  
            maxx=t[i];  
        }  
    }  
    printf("%d\n",ans);  
    for(int i=n;i>=1;i--)  
    {  
        if(t[i]==maxx)  
        {  
            s.push(i);  
            maxx--;  
        }  
    }  
    for(int i=0;i<ans;i++)  
    {  
        if(i!=0)printf(" ");  
        printf("%d",s.top());  
        s.pop();  
    }  
    printf("\n");  
}  

codeforce 977 F. Consecutive Subsequence