update script

Author: charliesbot

compile_flags.txt

@@ -0,0 +1 @@
+-std=c++17

cpp/0021_merge_two_sorted_lists/0021_merge_two_sorted_lists.h

@@ -0,0 +1,40 @@
+#include <iostream>
+#include <memory>
+
+struct ListNode {
+  int val;
+  ListNode *next;
+  ListNode() : val(0), next(nullptr) {}
+  ListNode(int x) : val(x), next(nullptr) {}
+  ListNode(int x, ListNode *next) : val(x), next(next) {}
+};
+
+class Solution {
+public:
+  ListNode *mergeTwoLists(ListNode *l1, ListNode *l2) {
+    ListNode *l3 = new ListNode();
+    ListNode *head = l3;
+
+    while (l1 && l2) {
+      if (l1->val <= l2->val) {
+        l3->next = l1;
+        l1 = l1->next;
+      } else {
+        l3->next = l2;
+        l2 = l2->next;
+      }
+
+      l3 = l3->next;
+    }
+
+    if (l1 != nullptr) {
+      l3->next = l1;
+    }
+
+    if (l2 != nullptr) {
+      l3->next = l2;
+    }
+
+    return head->next;
+  }
+};

cpp/0021_merge_two_sorted_lists/0021_merge_two_sorted_lists_test.cc

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+/* Given two non-negative integers num1 and num2 represented as strings,
+ * return the product of num1 and num2, also represented as a string.
+ */
+
+#include <string>
+#include <math.h>
+#include <vector>
+#include <algorithm>
+
+using std::string;
+
+class Solution {
+public:
+  string multiply(string num1, string num2) {
+    std::vector<int> result(num1.length() + num2.length(), 0);
+
+    int flag = 0;
+
+    for (int index1 = num1.length() - 1; index1 >= 0; index1--) {
+      int carry = 0;
+      int result_index = 0;
+      for (int index2 = num2.length() - 1; index2 >= 0; index2--) {
+        const int& raw_result = num1[index1] * num2[index2] + carry + result[result_index + flag];
+        result[result_index +flag] = raw_result % 10;
+        carry = floor(raw_result / 10);
+        result_index++;
+      }
+      flag++;
+    }
+
+    while(result.size() > 1) {
+      if (result.back() > 0) {
+        break;
+      }
+      result.pop_back();
+    }
+
+    std::reverse(result.begin(), result.end());
+
+    string string_result = "";
+
+    for(const int& letter: result) {
+      string_result += std::to_string(letter);
+    }
+
+    return string_result;
+  }
+};
+
+/*
+ 32
+219
+---
+carry = 0
+
+[8, 0, 0, 7, 0]
+
+7008
+*/

cpp/0043_multiply_strings/0043_multiply_strings.h

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+import { multiply } from "./0043_multiply_strings";
+
+test("multiply1", () => {
+  expect(multiply("2", "3")).toEqual("6");
+});
+
+test("multiply2", () => {
+  expect(multiply("589", "24")).toBe("14136");
+});
+
+test("multiply3", () => {
+  expect(multiply("5891", "243")).toBe("1431513");
+});
+
+test("multiply4", () => {
+  expect(multiply("123", "456")).toEqual("56088");
+});
+
+test("multiply5", () => {
+  expect(multiply("0", "0")).toEqual("0");
+});