Apply operations to make all array elements equal to zero

Array Prefix Sum

33.3% acceptance

Feb 25, 2026

447

You are given a 0-indexed integer array nums and a positive integer k. You can apply the following operation on the array any number of times: Choose any subarray of size k from the array and decrease all its elements by 1. Return true if you can make all the array elements equal to 0, or false otherwise. A subarray is a contiguous non-empty part of an array.

Solution

Rust

Time O(n)

Space O(n)

LeetCode

solution.rs

impl Solution {
  pub fn check_array(nums: Vec<i32>, k: i32) -> bool {
    let n = nums.len();
    let k = k as usize;
    // ops[i] is used as difference array for operations starting at each position
    let mut ops = vec![0i64; n + 1];
    let mut cur_ops = 0i64;
    for i in 0..n {
      cur_ops += ops[i];
      let need = nums[i] as i64 - cur_ops;
      if need < 0 { return false; }
      if need > 0 {
        if i + k > n { return false; }
        cur_ops += need;
        ops[i + k] -= need;
      }
    }
    true
  }
}