feat: add solutions to lc problem: No.0831

Author: thinkasany

solution/0800-0899/0831.Masking Personal Information/README.md

@@ -227,6 +227,30 @@ func maskPII(s string) string {
 }
 ```
 
+### **TypeScript**
+
+```ts
+function maskPII(s: string): string {
+    const i = s.indexOf('@');
+    if (i !== -1) {
+        let ans = s[0].toLowerCase() + '*****';
+        for (let j = i - 1; j < s.length; ++j) {
+            ans += s.charAt(j).toLowerCase();
+        }
+        return ans;
+    }
+    let t = '';
+    for (const c of s) {
+        if (/\d/.test(c)) {
+            t += c;
+        }
+    }
+    const cnt = t.length - 10;
+    const suf = `***-***-${t.substring(t.length - 4)}`;
+    return cnt === 0 ? suf : `+${'*'.repeat(cnt)}-${suf}`;
+}
+```
+
 ### **...**
 
 ```

solution/0800-0899/0831.Masking Personal Information/README_EN.md

@@ -196,6 +196,30 @@ func maskPII(s string) string {
 }
 ```
 
+### **TypeScript**
+
+```ts
+function maskPII(s: string): string {
+    const i = s.indexOf('@');
+    if (i !== -1) {
+        let ans = s[0].toLowerCase() + '*****';
+        for (let j = i - 1; j < s.length; ++j) {
+            ans += s.charAt(j).toLowerCase();
+        }
+        return ans;
+    }
+    let t = '';
+    for (const c of s) {
+        if (/\d/.test(c)) {
+            t += c;
+        }
+    }
+    const cnt = t.length - 10;
+    const suf = `***-***-${t.substring(t.length - 4)}`;
+    return cnt === 0 ? suf : `+${'*'.repeat(cnt)}-${suf}`;
+}
+```
+
 ### **...**
 
 ```

solution/0800-0899/0831.Masking Personal Information/Solution.ts

@@ -0,0 +1,19 @@
+function maskPII(s: string): string {
+    const i = s.indexOf('@');
+    if (i !== -1) {
+        let ans = s[0].toLowerCase() + '*****';
+        for (let j = i - 1; j < s.length; ++j) {
+            ans += s.charAt(j).toLowerCase();
+        }
+        return ans;
+    }
+    let t = '';
+    for (const c of s) {
+        if (/\d/.test(c)) {
+            t += c;
+        }
+    }
+    const cnt = t.length - 10;
+    const suf = `***-***-${t.substring(t.length - 4)}`;
+    return cnt === 0 ? suf : `+${'*'.repeat(cnt)}-${suf}`;
+}