feat: add typescript solution to lc problem: No.2156

No.2156.Find Substring With Given Hash Value

Author: zhaocchen

solution/2100-2199/2156.Find Substring With Given Hash Value/README.md

@@ -74,10 +74,46 @@
 
 ```
 
-### **TypeScript**
-
-```ts
-
+### **JavaScript**
+
+```js
+/**
+ * @param {string} s
+ * @param {number} power
+ * @param {number} modulo
+ * @param {number} k
+ * @param {number} hashValue
+ * @return {string}
+ */
+var subStrHash = function(s, power, modulo, k, hashValue) {
+    power = BigInt(power);
+    modulo = BigInt(modulo); 
+    hashValue = BigInt(hashValue);
+    const n = s.length;
+    let pk = 1n;
+    let ac = 0n;
+    // 倒序滑动窗口
+    for (let i = n - 1; i > n - 1 - k; i--) {
+        ac = (ac * power + getCode(s, i)) % modulo;
+        pk = pk * power % modulo;
+    }
+    let ans = -1;
+    if (ac == hashValue) {
+        ans = n - k;
+    }
+    for (let i = n - 1 - k; i >= 0; i--) {
+        let pre = getCode(s, i + k) * pk % modulo;
+        ac = (ac * power + getCode(s, i) - pre + modulo) % modulo;
+        if (ac == hashValue) {
+            ans = i;
+        }
+    }
+    return ans == -1 ? '' : s.substring(ans, ans + k);
+};
+
+function getCode(str, index) {
+    return BigInt(str.charCodeAt(index) - 'a'.charCodeAt(0) + 1);
+}
 ```
 
 ### **...**

solution/2100-2199/2156.Find Substring With Given Hash Value/README_EN.md

@@ -66,10 +66,46 @@ Note that "bxz" also has a hash of 32 but it appears later than "
 
 ```
 
-### **TypeScript**
-
-```ts
-
+### **JavaScript**
+
+```js
+/**
+ * @param {string} s
+ * @param {number} power
+ * @param {number} modulo
+ * @param {number} k
+ * @param {number} hashValue
+ * @return {string}
+ */
+var subStrHash = function(s, power, modulo, k, hashValue) {
+    power = BigInt(power);
+    modulo = BigInt(modulo); 
+    hashValue = BigInt(hashValue);
+    const n = s.length;
+    let pk = 1n;
+    let ac = 0n;
+    // 倒序滑动窗口
+    for (let i = n - 1; i > n - 1 - k; i--) {
+        ac = (ac * power + getCode(s, i)) % modulo;
+        pk = pk * power % modulo;
+    }
+    let ans = -1;
+    if (ac == hashValue) {
+        ans = n - k;
+    }
+    for (let i = n - 1 - k; i >= 0; i--) {
+        let pre = getCode(s, i + k) * pk % modulo;
+        ac = (ac * power + getCode(s, i) - pre + modulo) % modulo;
+        if (ac == hashValue) {
+            ans = i;
+        }
+    }
+    return ans == -1 ? '' : s.substring(ans, ans + k);
+};
+
+function getCode(str, index) {
+    return BigInt(str.charCodeAt(index) - 'a'.charCodeAt(0) + 1);
+}
 ```
 
 ### **...**

solution/2100-2199/2156.Find Substring With Given Hash Value/Solution.js

@@ -0,0 +1,37 @@
+/**
+ * @param {string} s
+ * @param {number} power
+ * @param {number} modulo
+ * @param {number} k
+ * @param {number} hashValue
+ * @return {string}
+ */
+ var subStrHash = function(s, power, modulo, k, hashValue) {
+    power = BigInt(power);
+    modulo = BigInt(modulo); 
+    hashValue = BigInt(hashValue);
+    const n = s.length;
+    let pk = 1n;
+    let ac = 0n;
+    // 倒序滑动窗口
+    for (let i = n - 1; i > n - 1 - k; i--) {
+        ac = (ac * power + getCode(s, i)) % modulo;
+        pk = pk * power % modulo;
+    }
+    let ans = -1;
+    if (ac == hashValue) {
+        ans = n - k;
+    }
+    for (let i = n - 1 - k; i >= 0; i--) {
+        let pre = getCode(s, i + k) * pk % modulo;
+        ac = (ac * power + getCode(s, i) - pre + modulo) % modulo;
+        if (ac == hashValue) {
+            ans = i;
+        }
+    }
+    return ans == -1 ? '' : s.substring(ans, ans + k);
+};
+
+function getCode(str, index) {
+    return BigInt(str.charCodeAt(index) - 'a'.charCodeAt(0) + 1);
+}