[ICPC 2018 Qingdao R] Function and Function

Luogu
IDLGP9897
Time1000ms
Memory256MB
DifficultyP2
2018O2优化ICPC青岛
If we define $f(0) = 1, f(1) = 0, f(4) = 1, f(8) = 2, f(16) = 1, \dots$, do you know what function $f$ means? Actually, $f(x)$ calculates the total number of enclosed areas produced by each digit in $x$. The following table shows the number of enclosed areas produced by each digit: ![](https://cdn.luogu.com.cn/upload/image_hosting/sdv14tzu.png) For example, $f(1234) = 0 + 0 + 0 + 1 = 1$, and $f(5678) = 0 + 1 + 0 + 2 = 3$. We now define a recursive function $g$ by the following equations: $$\begin{cases} g^0(x) = x \\ g^k(x) = f(g^{k-1}(x)) & \text{if } k \ge 1 \end{cases}$$ For example, $g^2(1234) = f(f(1234)) = f(1) = 0$, and $g^2(5678) = f(f(5678)) = f(3) = 0$. Given two integers $x$ and $k$, please calculate the value of $g^k(x)$. ## Input There are multiple test cases. The first line of the input contains an integer $T$ (about $10^5$), indicating the number of test cases. For each test case: The first and only line contains two integers $x$ and $k$ ($0 \le x, k \le 10^9$). Positive integers are given without leading zeros, and zero is given with exactly one `0'. ## Output For each test case output one line containing one integer, indicating the value of $g^k(x)$. [samples] ## Note ![](https://cdn.luogu.com.cn/upload/image_hosting/fjjr5xin.png)
Samples
Input #1
6
123456789 1
888888888 1
888888888 2
888888888 999999999
98640 12345
1000000000 0
Output #1
5
18
2
0
0
1000000000
API Response (JSON)
{
  "problem": {
    "name": "[ICPC 2018 Qingdao R] Function and Function",
    "description": {
      "content": "If we define $f(0) = 1, f(1) = 0, f(4) = 1, f(8) = 2, f(16) = 1, \\dots$, do you know what function $f$ means? Actually, $f(x)$ calculates the total number of enclosed areas produced by each digit in ",
      "description_type": "Markdown"
    },
    "platform": "Luogu",
    "limit": {
      "time_limit": 1000,
      "memory_limit": 262144
    },
    "difficulty": {
      "LuoguStyle": "P2"
    },
    "is_remote": true,
    "is_sync": true,
    "sync_url": null,
    "sign": "LGP9897"
  },
  "statements": [
    {
      "statement_type": "Markdown",
      "content": "If we define $f(0) = 1, f(1) = 0, f(4) = 1, f(8) = 2, f(16) = 1, \\dots$, do you know what function $f$ means?\n\nActually, $f(x)$ calculates the total number of enclosed areas produced by each digit in ...",
      "is_translate": false,
      "language": "English"
    }
  ]
}
Full JSON Raw Segments