Edit Distance

Edit Distance

	// vim: syntax=swift
func minDistance(_ word1: String, _ word2: String) -> Int {
    guard word1.count > 0 && word2.count > 0 else{
        return max(word1.count,word2.count)
    }
    let w1 = Array(word1), w2 = Array(word2), row = w2.count, col = w1.count
    var dp = Array(repeating: Array(repeating: 0, count: col+1), count: row+1)
    for i in 1..<dp[0].count{
        dp[0][i] = i
    }
    for i in 1..<dp.count{
        dp[i][0] = i
    }
    for i in 1...row{
        for j in 1...col{
            if w2[i-1] == w1[j-1]{
                dp[i][j] = dp[i-1][j-1]
            }else{
                dp[i][j] = min(dp[i-1][j-1], dp[i-1][j], dp[i][j-1]) + 1
            }
        }
    }
    return dp[row][col]
}