2996. 大于等于顺序前缀和的最小缺失整数

src/main.rs

@@ -1,27 +1,21 @@
+use std::collections::HashSet;
+
 mod arr;
 struct Solution {}
 impl Solution {
-    pub fn count_majority_subarrays(nums: Vec<i32>, target: i32) -> i64 {
-        let mut arr: Vec<i32> = vec![0; nums.len() + 1];
-        for i in 0..nums.len() {
-            arr[i + 1] = arr[i] + if nums[i] == target { 1 } else { -1 };
-        }
-        // [-n, n] -> [0, 2n]
-        let n = nums.len() as i32;
-        let mut pre = vec![0; nums.len() * 2 + 1];
-        let mut presum = 0;
-        let mut ans = 0;
-        println!("{:?}", arr);
-        for r in 0..nums.len() {
-            pre[(arr[r] + n) as usize] += 1;
-            if arr[r + 1] > arr[r] {
-                presum += pre[(arr[r] + n) as usize];
-            } else {
-                presum = (presum - pre[(arr[r + 1] + n) as usize]).max(0);
+    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;
             }
-            ans += presum;
+            sum += nums[i];
         }
-        ans
+        while st.contains(&sum) {
+            sum += 1;
+        }
+        sum
     }
 }
 fn main() {
@@ -29,6 +23,6 @@ fn main() {
     //  0  -1   0   1   0
     println!(
         "{:?}",
-        Solution::count_majority_subarrays(vec![1, 2, 2, 3], 2)
+        Solution::missing_integer(vec![14,9,6,9,7,9,10,4,9,9,4,4])
     );
 }