Maximum number of matching indices after right shifts

Array Two Pointers Simulation

84.8% acceptance

Mar 31, 2026

You are given two integer arrays, nums1 and nums2, of the same length. An index i is considered matching if nums1[i] == nums2[i]. Return the maximum number of matching indices after performing any number of right shifts on nums1. A right shift is defined as shifting the element at index i to index (i + 1) % n, for all indices.

Solution

Rust

Time O(n²)

Space O(1)

LeetCode

solution.rs

impl Solution {
  pub fn maximum_matching_indices(nums1: Vec<i32>, nums2: Vec<i32>) -> i32 {
    let n = nums1.len();
    let mut best = 0;
    for shift in 0..n {
      let mut count = 0;
      for i in 0..n {
        if nums1[(i + n - shift) % n] == nums2[i] {
          count += 1;
        }
      }
      best = best.max(count);
    }
    best
  }
}