3381. 长度可被 K 整除的子数组的最大元素和

src/main.rs

@@ -1,30 +1,27 @@
-use crate::arr::make_matrix;
+use std::cmp::max;
 
 struct Solution;
 mod arr;
 impl Solution {
-    pub fn number_of_paths(grid: Vec<Vec<i32>>, k: i32) -> i32 {
-        let mut arr = vec![vec![vec![0; k as usize]; grid[0].len()]; grid.len()];
-        let r#mod = 1e9 as i32 + 7;
-        arr[0][0][(grid[0][0] % k) as usize] = 1;
-        for i in 0..grid.len() {
-            for j in 0..grid[i].len() {
-                if i < grid.len() - 1 {
-                    for l in 0..k {
-                        arr[i + 1][j][((l + grid[i + 1][j]) % k) as usize] = (arr[i + 1][j][((l + grid[i + 1][j]) % k) as usize] + arr[i][j][l as usize]) % r#mod;
+    pub fn max_subarray_sum(nums: Vec<i32>, k: i32) -> i64 {
+        let mut temp = 0_i64;
+        let k = k as usize;
+        let mut dp = vec![0_i64; nums.len()];
+        let mut ans = 0_i64;
+        for i in 0..k {
+            temp += nums[i] as i64;
         }
+        dp[k - 1] = temp;
+        ans = temp;
+        for i in k..nums.len() {
+            temp = temp + (nums[i] - nums[i - k]) as i64;
+            dp[i] = temp + if dp[i-k] > 0 { dp[i-k] } else { 0 };
+            ans = max(ans,dp[i]);
         }
-                if j < grid[0].len() - 1 {
-                    for l in 0..k {
-                        arr[i][j + 1][((l + grid[i][j + 1]) % k) as usize] = (arr[i][j + 1][((l + grid[i][j + 1]) % k) as usize] + arr[i][j][l as usize]) % r#mod;
-                    }
-                }
-            }
-        }
-        arr[grid.len() - 1][grid[0].len() - 1][0]
+        ans
     }
 }
 fn main() {
-    let result = Solution::number_of_paths(make_matrix("[[5,2,4],[3,0,5],[0,7,2]]"), 3);
+    let result = Solution::max_subarray_sum(vec![-5,1,2,-3,4],2);
     println!("{:?}", result);
 }