两个字符串的最小ASCII删除和

两个字符串的最小ASCII删除和

https://leetcode-cn.com/problems/delete-operation-for-two-strings/

跟编辑距离几乎是一样的，只是把操作数换成 ASCII 码罢了。

动态规划

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func minimumDeleteSum(s1 string, s2 string) int {
    m := len(s1)
    n := len(s2)
    dp := make([][]int, m + 1)
    for i := range dp {
        dp[i] = make([]int, n + 1)
    }

    for i := 1; i <= m; i++ {
        dp[i][0] = dp[i-1][0] + int(s1[i-1])
    }
    for j := 1; j <= n; j++ {
        dp[0][j] = dp[0][j-1] + int(s2[j-1])
    }

    for i := 1; i <= m; i++ {
        for j := 1; j <= n; j++ {
            if s1[i-1] == s2[j-1] {
                dp[i][j] = dp[i-1][j-1]
            } else {
                dp[i][j] = min(dp[i-1][j]+int(s1[i-1]), dp[i][j-1]+int(s2[j-1]))
            }
        }
    }

    return dp[m][n]
}

func min(a int, b int) int {
    if a < b {
        return a
    }
    return b
}