HDU 5062 beautiful palindrome number (bestcodeer round #13)

Beautiful palindrome number Time Limit: 3000/1500 MS (Java/others) memory limit: 32768/32768 K (Java/Others)
Total submission (s): 116 accepted submission (s): 82


Problem descriptiona positive integer x can represent (A1a2... Akak... A2a1) 10 Or (A1a2... AK? 1 Akak? 1... A2a1) 10 Of a 10-based notational system, we always call X is a palindrome number. If it satisfies 0 <A1 <A2 <... <Ak ≤ 9 , We call X is a beautiful palindrome number.
Now, we want to know how many beautiful palindrome numbers are between 1 and 10n .
Inputthe first line in the input file is an integer T (1 ≤ T ≤ 7) , Indicating the number of test cases.
Then T lines follow, each line represent an integer N (0 ≤ n ≤ 6) .
Outputfor each test case, output the number of beautiful palindrome number.
Sample Input

216

Sample output

9258

Sourcebestcoder round #13
There are only seven results. Just hand in a table. The maximum number of N is 6, and the brute-force code is acceptable. Attach the tabulation code and brute force code.
Code for table creation:

//0ms#include <cstdio>#include <cstring>#include <iostream>int a[7]={1,9,18,54,90,174,258};int main(){    int t,n;    scanf("%d",&t);    while(t--)    {        scanf("%d",&n);        printf("%d\n",a[n]);    }}

Brute force code:

//46ms#include <iostream>#include <cstdio>#include <cstring>#include <algorithm>using namespace std;int a[10];bool judge(int x){    int n=0;    while(x>0)    {        a[++n]=x%10;        x=x/10;    }    //printf("%d\n",n);    if(a[1]!=a[n])    return false;    for(int j=2,k=n-1;j<=k;j++,k--)    {        if(a[j]>a[j-1]&&a[j]==a[k])        ;        else        return false;    }    return true;}int main(){    int t,n;    scanf("%d",&t);    while(t--)    {        scanf("%d",&n);        int temp=1;        int ans=0;        for(int i=1;i<=n;i++)        {            temp*=10;        }        //printf("%d",temp);        for(int i=1;i<=temp;i++)        {            if(judge(i))            {                ans++;            }        }        printf("%d\n",ans);    }    return 0;}

HDU 5062 beautiful palindrome number (bestcodeer round #13)