complete 5369.rs 11689.rs 15649.rs

storage/zeta/rs/completed/15649.rs

@@ -0,0 +1,58 @@
+use std::io::{BufWriter, stdin, Write};
+enum Operation {
+    VisIn,
+    VisOut
+}
+
+fn main() {
+    let mut line = String::new();
+    stdin().read_line(&mut line).unwrap();
+    let mut out = BufWriter::new(std::io::stdout());
+    let mut iter = line
+        .trim()
+        .split(' ')
+        .map(|x| x.trim().parse::<u64>().unwrap());
+
+    let n = iter.next().unwrap();
+    let m = iter.next().unwrap();
+
+    let mut vis = vec![false; n as usize];
+    let mut arr: Vec<u64> = vec![];
+    let mut stack: Vec<(Operation, u64)> = vec![];
+
+    for i in (0..n).rev() {
+        stack.push((Operation::VisOut, i));
+        stack.push((Operation::VisIn, i));
+    }
+
+    while !stack.is_empty() {
+        let item = stack.pop().unwrap();
+        match item.0 {
+            Operation::VisIn => {
+                arr.push(item.1);
+                if arr.len() == m as usize {
+                    for &val in &arr {
+                        write!(out, "{} ", val + 1).unwrap();
+                    }
+                    writeln!(out, "").unwrap();
+                    continue;
+                }
+                let idx = item.1 as usize;
+
+                vis[idx] = true;
+                for j in (0..n).rev() {
+                    if !vis[j as usize] {
+                        stack.push((Operation::VisOut, j));
+                        stack.push((Operation::VisIn, j));
+                    }
+                }
+            }
+            Operation::VisOut => {
+                let idx = item.1 as usize;
+                vis[idx] = false;
+                arr.pop();
+            }
+        }
+
+    }
+}