57 lines
1.2 KiB
Rust
57 lines
1.2 KiB
Rust
/**
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* [207] Course Schedule
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*/
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pub struct Solution {}
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// submission codes start here
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use std::collections::VecDeque;
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impl Solution {
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pub fn can_finish(num_courses: i32, prerequisites: Vec<Vec<i32>>) -> bool {
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let num_courses = num_courses as usize;
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let mut edges = vec![vec![];num_courses];
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let mut in_degs = vec![0;num_courses];
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for edge in prerequisites {
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edges[edge[1] as usize].push(edge[0] as usize);
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in_degs[edge[0] as usize] += 1;
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}
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let mut queue = VecDeque::new();
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for i in 0..num_courses {
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if in_degs[i] == 0 {
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queue.push_back(i);
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}
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}
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let mut visited = 0;
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while !queue.is_empty() {
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let node = queue.pop_front().unwrap();
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visited += 1;
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for next_node in &edges[node] {
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in_degs[*next_node] -= 1;
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if in_degs[*next_node] == 0 {
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queue.push_back(*next_node);
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}
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}
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}
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visited == num_courses
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}
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}
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// submission codes end
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#[cfg(test)]
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mod tests {
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use super::*;
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#[test]
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fn test_207() {
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}
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}
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