diff --git a/problems/0115.不同的子序列.md b/problems/0115.不同的子序列.md index 0f762969..ca66e20d 100644 --- a/problems/0115.不同的子序列.md +++ b/problems/0115.不同的子序列.md @@ -267,6 +267,36 @@ const numDistinct = (s, t) => { }; ``` +TypeScript: + +```typescript +function numDistinct(s: string, t: string): number { + /** + dp[i][j]: s前i个字符,t前j个字符,s子序列中t出现的个数 + dp[0][0]=1, 表示s前0个字符为'',t前0个字符为'' + */ + const sLen: number = s.length, + tLen: number = t.length; + const dp: number[][] = new Array(sLen + 1).fill(0) + .map(_ => new Array(tLen + 1).fill(0)); + for (let m = 0; m < sLen; m++) { + dp[m][0] = 1; + } + for (let i = 1; i <= sLen; i++) { + for (let j = 1; j <= tLen; j++) { + if (s[i - 1] === t[j - 1]) { + dp[i][j] = dp[i - 1][j - 1] + dp[i - 1][j]; + } else { + dp[i][j] = dp[i - 1][j]; + } + } + } + return dp[sLen][tLen]; +}; +``` + + + -----------------------