877. 石子游戏

src/main.rs

@@ -3,24 +3,31 @@ use std::collections::HashSet;
 mod arr;
 struct Solution {}
 impl Solution {
-    pub fn missing_integer(nums: Vec<i32>) -> i32 {
-        let mut st = nums.clone().into_iter().collect::<HashSet<i32>>();
-        let mut sum = nums[0];
-        for i in 1 .. nums.len() {
-            if nums[i] != nums[i-1] + 1 {
-                break;
+    pub fn stone_game(piles: Vec<i32>) -> bool {
+        return true;
+        let mut mem = vec![vec![vec![]; piles.len()]; piles.len()];
+        // a do alice bob; b do alice bob
+        for j in 0..(piles.len() - 1) {
+            mem[j][j + 1] = if piles[j] > piles[j + 1] {
+                vec![piles[j], piles[j + 1]]
+            } else {
+                vec![piles[j + 1], piles[j]]
+            };
         }
-            sum += nums[i];
+        for i in 2..piles.len() {
+            for j in 0..(piles.len() - i) {
+                mem[j][j+i] = if mem[j][j + i - 1][1] - mem[j][j + i - 1][0] + piles[j + i]
+                    > mem[j + 1][j + i][1] - mem[j + 1][j + i][0] + piles[j]
+                {
+                    vec![mem[j][j + i - 1][1] + piles[j + i], mem[j][j + i - 1][0]]
+                } else {
+                    vec![mem[j + 1][j + i][1] + piles[j], mem[j + 1][j + i][0]]
+                };
             }
-        while st.contains(&sum) {
-            sum += 1;
         }
-        sum
+        mem[0][piles.len() - 1][0] >mem[0][piles.len() - 1][1]
     }
 }
 fn main() {
-    println!(
-        "{:?}",
-        Solution::missing_integer(vec![14,9,6,9,7,9,10,4,9,9,4,4])
-    );
+    println!("{:?}", Solution::stone_game(vec![1,5,1]));
 }