complete 1766.rs

storage/zeta/rs/1766.rs

@@ -0,0 +1,70 @@
+use std::cmp::Reverse;
+use std::collections::BinaryHeap;
+use std::io;
+
+fn split_by_2(s: &str) -> (usize, usize) {
+    let mut iter = s.split_ascii_whitespace();
+    (
+        iter.next().unwrap().parse().unwrap(),
+        iter.next().unwrap().parse().unwrap(),
+    )
+}
+
+fn get_order(n: usize, precedents: Vec<(usize, usize)>) -> Vec<usize> {
+    let mut order = Vec::new();
+
+    let mut graph: Vec<Vec<usize>> = vec![Vec::new(); n];
+
+    let mut indeg = vec![0; n];
+
+    let mut queue = BinaryHeap::new();
+
+    for (prec, succ) in precedents {
+        indeg[succ - 1] += 1;
+        graph[prec - 1].push(succ - 1);
+    }
+    for i in 0..n {
+        graph[i].sort();
+    }
+
+    for (i, indeg) in indeg.iter().enumerate() {
+        if *indeg == 0 {
+            queue.push(Reverse(i));
+        }
+    }
+
+    while !queue.is_empty() {
+        let now = queue.pop().unwrap().0;
+        order.push(now);
+
+        for succ in graph[now].iter() {
+            indeg[*succ] -= 1;
+            if indeg[*succ] == 0 {
+                queue.push(Reverse(*succ));
+            }
+        }
+    }
+
+    order
+}
+
+fn main() {
+    let mut line = String::new();
+    io::stdin().read_line(&mut line).unwrap();
+    let (n, m): (usize, usize);
+    (n, m) = split_by_2(&line);
+    let precedents: Vec<(usize, usize)>;
+
+    precedents = (0..m)
+        .map(|_| {
+            let mut line = String::new();
+            io::stdin().read_line(&mut line).unwrap();
+            split_by_2(&line)
+        })
+        .collect();
+
+    get_order(n, precedents)
+        .into_iter()
+        .for_each(|i| print!("{} ", i + 1));
+    println!();
+}