Excel sheet column number

Math String

67.3% acceptance

Jan 12, 2026

5078

399

Given a string columnTitle that represents the column title as appears in an Excel sheet, return its corresponding column number. For example: A -> 1 B -> 2 C -> 3 ... Z -> 26 AA -> 27 AB -> 28 ...

Solution

Rust

Time O(n)

Space O(1)

LeetCode

solution.rs

impl Solution {
  pub fn title_to_number(column_title: String) -> i32 {
    let mut result = 0;
    
    for ch in column_title.chars() {
      result = result * 26 + (ch as i32 - 'A' as i32 + 1);
    }
    
    result
  }
}