codeforces Perfect Number（暴力）

B. Perfect Number

time limit per test

2 seconds

memory limit per test

256 megabytes

input

standard input

output

standard output

We consider a positive integer perfect, if and only if the sum of its digits is exactly 10. Given a positive integer k, your task is to find the k-th smallest perfect positive integer.

Input

A single line with a positive integer k (1 ≤ k ≤ 10 000).

Output

A single number, denoting the k-th smallest perfect integer.

Examples

input

1

output

19

input

2

output

28

Note

The first perfect integer is 19 and the second one is 28.

题意很简单

求出第K个所有位数加起来和为10的数字

暴力的同时计数

数据为10000时对应的数字是10800100

复杂度O(n)，可以卡过

#include
#include
#include
#include
#define maxn 10800100

int juge(int a){
    int i = 0,cnt = 0;
    while(a > 0){
        cnt += a%10;
        a/=10;
    }
    return cnt==10?1:0;
}

int main()
{
    int cnt=0,i,n;
    scanf("%d",&n);
    for(i = 9;i <= maxn;i++){//个位数不可能是完美数，其实应该直接从19开始打表
        if(juge(i))
            cnt++;
    if(cnt == n)
        break;
    }
    printf("%d",i);
    return 0;
}

转载于:https://www.cnblogs.com/bestsort/p/10588913.html