first two problems solved

2023_09_18/maximum_subarray/src/main.rs

@@ -0,0 +1,22 @@
+// Given an integer array nums, find the subarray  with the largest sum, and return its sum.
+// https://leetcode.com/problems/maximum-subarray/description/
+
+fn max_sub_array(nums: &[i32]) -> i32 {
+    let mut max_ending_here = nums[0];
+    let mut max_so_far = nums[0];
+
+    for &num in nums.iter().skip(1) {
+        // What is the maximum sum of the subarray ending at this point?
+        max_ending_here = i32::max(num, max_ending_here + num);
+        // What is the maximum sum of any subarray we've seen so far?
+        max_so_far = i32::max(max_so_far, max_ending_here);
+    }
+
+    max_so_far
+}
+
+fn main() {
+    let nums = [-2, 1, -3, 4, -1, 2, 1, -5, 4];
+    let res = maxSubArray(&nums);
+    println!("{}", res);
+}