Leet Code Daily 2024-06-03 - Append Characters to String to Make Subsequence

constexpr int kMaxSize = 100001;
constexpr int kNumChars = 26;

class Solution {
public:
    int appendCharacters(string s, string t) {
        int n = s.size(), m = t.size();
        int i = 0, j = 0;
        while (i < n && j < m) {
            if (s[i] == t[j]) {
                j++;
            }
            i++;
        }
        return m - j;
    }
};