leetcode: Add 0055

src/leetcode/0055.jump-game/Cargo.toml

@@ -0,0 +1,7 @@
+[package]
+name = "lc-0055-jump-game"
+version = "0.1.0"
+edition = "2021"
+publish = false
+
+[dependencies]

src/leetcode/0055.jump-game/index.md

@@ -0,0 +1,4 @@
+
+# 
+
+[问题描述](../problems/)

src/leetcode/0055.jump-game/src/main.rs

@@ -0,0 +1,82 @@
+// Copyright (c) 2024 Xu Shaohua <[email protected]>. All rights reserved.
+// Use of this source is governed by General Public License that can be found
+// in the LICENSE file.
+
+// Greedy
+pub fn can_jump1(nums: Vec<i32>) -> bool {
+    debug_assert!((1..=10_000).contains(&nums.len()));
+
+    // 最远跳跃距离
+    let mut max_pos: usize = 0;
+
+    for (index, &num) in nums.iter().enumerate() {
+        let num_usize: usize = num as usize;
+
+        // max_pos >= index, 表示能从之前的节点跳到这里.
+        // index + num_usize > max_pos, 表示基于当前的点, 可以跳得更远.
+        if max_pos >= index && index + num_usize > max_pos {
+            // 更新最远跳跃距离
+            max_pos = index + num_usize;
+        }
+    }
+    // 是否遍历完数组, 到达最远的位置
+    max_pos + 1 >= nums.len()
+}
+
+pub fn can_jump2(nums: Vec<i32>) -> bool {
+    debug_assert!((1..=10_000).contains(&nums.len()));
+
+    // 最远跳跃距离
+    let mut max_pos: usize = 0;
+
+    for (index, &num) in nums.iter().enumerate() {
+        // index > max_pos, 表示能从之前的节点无法跳到这里.
+        if index > max_pos {
+            return false;
+        }
+
+        // index + num_usize > max_pos, 表示基于当前的点, 可以跳得更远.
+        let num_usize: usize = num as usize;
+        if max_pos >= index && index + num_usize > max_pos {
+            // 更新最远跳跃距离.
+            max_pos = index + num_usize;
+
+            // 如果这次跳得足够远, 超过了数组长度, 就直接提前返回 true.
+            if max_pos + 1 >= nums.len() {
+                return true;
+            }
+        }
+    }
+
+    true
+}
+
+pub type SolutionFn = fn(Vec<i32>) -> bool;
+
+fn check_can_jump(func: SolutionFn) {
+    let nums = vec![2, 3, 1, 1, 4];
+    assert!(func(nums));
+
+    let nums = vec![3, 2, 1, 0, 4];
+    assert!(!func(nums));
+}
+
+fn main() {
+    check_can_jump(can_jump1);
+    check_can_jump(can_jump2);
+}
+
+#[cfg(test)]
+mod tests {
+    use super::{can_jump1, can_jump2, check_can_jump};
+
+    #[test]
+    fn test_can_jump1() {
+        check_can_jump(can_jump1);
+    }
+
+    #[test]
+    fn test_can_jump2() {
+        check_can_jump(can_jump2);
+    }
+}