Datasets:
Tasks:
Text Generation
Modalities:
Text
Formats:
json
Languages:
English
Size:
< 1K
ArXiv:
Tags:
competitive-programming
code-generation
specification-generation
proof-generation
verification
rust
License:
| use vstd::prelude::*; | |
| fn main() {} | |
| verus! { | |
| pub struct Solution; | |
| impl Solution { | |
| pub open spec fn circular_sum(code: Seq<i32>, n: int, start: int, count: int) -> int | |
| decreases count, | |
| { | |
| if count <= 0 || n <= 0 { | |
| 0 | |
| } else { | |
| code[start % n] as int + Self::circular_sum(code, n, start + 1, count - 1) | |
| } | |
| } | |
| pub open spec fn decrypt_val(code: Seq<i32>, n: int, k: int, i: int) -> int { | |
| if k > 0 { | |
| Self::circular_sum(code, n, i + 1, k) | |
| } else if k < 0 { | |
| Self::circular_sum(code, n, i + n + k, -k) | |
| } else { | |
| 0 | |
| } | |
| } | |
| pub fn decrypt(code: Vec<i32>, k: i32) -> (result: Vec<i32>) | |
| requires | |
| 1 <= code@.len() <= 100, | |
| forall|i: int| 0 <= i < code@.len() ==> 1 <= code@[i] <= 100, | |
| -(code@.len() as int - 1) <= k as int <= code@.len() as int - 1, | |
| ensures | |
| result@.len() == code@.len(), | |
| forall|i: int| | |
| 0 <= i < code@.len() ==> ( result@[i]) as int == Self::decrypt_val( | |
| code@, | |
| code@.len() as int, | |
| k as int, | |
| i, | |
| ), | |
| { | |
| let n = code.len(); | |
| let mut result: Vec<i32> = Vec::new(); | |
| if k == 0 { | |
| let mut i: usize = 0; | |
| while i < n { | |
| result.push(0); | |
| i = i + 1; | |
| } | |
| return result; | |
| } | |
| let mut sum: i32 = 0; | |
| if k > 0 { | |
| let mut j: usize = 0; | |
| while j < k as usize { | |
| sum = sum + code[(1 + j) % n]; | |
| j = j + 1; | |
| } | |
| result.push(sum); | |
| let mut i: usize = 1; | |
| while i < n { | |
| sum = sum - code[i % n] + code[(i + k as usize) % n]; | |
| result.push(sum); | |
| i = i + 1; | |
| } | |
| } else { | |
| let abs_k: usize = (-k) as usize; | |
| let mut j: usize = 0; | |
| while j < abs_k { | |
| sum = sum + code[(n - abs_k + j) % n]; | |
| j = j + 1; | |
| } | |
| result.push(sum); | |
| let mut i: usize = 1; | |
| while i < n { | |
| sum = sum - code[(i + n - abs_k - 1) % n] + code[(i + n - 1) % n]; | |
| result.push(sum); | |
| i = i + 1; | |
| } | |
| } | |
| result | |
| } | |
| } | |
| } | |