一刷415

Author: diguage

README.adoc

@@ -2930,13 +2930,13 @@ TIP: **公众号的微信号是: `jikerizhi`**。__因为众所周知的原因
 //|{doc_base_url}/0414-third-maximum-number.adoc[题解]
 //|Easy
 //|
-//
-//|{counter:codes}
-//|{leetcode_base_url}/add-strings/[415. Add Strings^]
-//|{source_base_url}/_0415_AddStrings.java[Java]
-//|{doc_base_url}/0415-add-strings.adoc[题解]
-//|Easy
-//|
+
+|{counter:codes}
+|{leetcode_base_url}/add-strings/[415. Add Strings^]
+|{source_base_url}/_0415_AddStrings.java[Java]
+|{doc_base_url}/0415-add-strings.adoc[题解]
+|Easy
+|
 
 |{counter:codes}
 |{leetcode_base_url}/partition-equal-subset-sum/[416. Partition Equal Subset Sum^]

docs/0415-add-strings.adoc

@@ -16,8 +16,24 @@ Given two non-negative integers `num1` and `num2` represented as string, return
 
 
 [[src-0415]]
+[tabs]
+====
+一刷::
++
+--
 [{java_src_attr}]
 ----
 include::{sourcedir}/_0415_AddStrings.java[tag=answer]
 ----
+--
+
+// 二刷::
+// +
+// --
+// [{java_src_attr}]
+// ----
+// include::{sourcedir}/_0415_AddStrings_2.java[tag=answer]
+// ----
+// --
+====
 

docs/index.adoc

@@ -904,7 +904,7 @@ include::0412-fizz-buzz.adoc[leveloffset=+1]
 
 // include::0414-third-maximum-number.adoc[leveloffset=+1]
 
-// include::0415-add-strings.adoc[leveloffset=+1]
+include::0415-add-strings.adoc[leveloffset=+1]
 
 include::0416-partition-equal-subset-sum.adoc[leveloffset=+1]
 

logbook/202406.adoc

@@ -803,6 +803,10 @@
 |{doc_base_url}/0392-is-subsequence.adoc[题解]
 |✅ 双指针
 
+|{counter:codes}
+|{leetcode_base_url}/add-strings/[415. Add Strings^]
+|{doc_base_url}/0415-add-strings.adoc[题解]
+|✅ 双指针，从后向前，模拟加法进位。
 
 |===
 

src/main/java/com/diguage/algo/leetcode/_0412_FizzBuzz.java

@@ -41,12 +41,15 @@
  * @since 2020-01-26 23:17
  */
 public class _0412_FizzBuzz {
-  // tag::answer[]
+    // tag::answer[]
 
     /**
      * Runtime: 2 ms, faster than 29.17% of Java online submissions for Fizz Buzz.
      *
      * Memory Usage: 45.5 MB, less than 5.40% of Java online submissions for Fizz Buzz.
+     *
+     * @author D瓜哥 · https://www.diguage.com
+     * @since 2020-01-26 23:17
      */
     public List<String> fizzBuzz(int n) {
         List<String> result = new ArrayList<>(n);
@@ -64,7 +67,7 @@ public List<String> fizzBuzz(int n) {
         return result;
     }
 
-  // end::answer[]
+    // end::answer[]
 
 
     public static void main(String[] args) {

src/main/java/com/diguage/algo/leetcode/_0415_AddStrings.java

@@ -0,0 +1,40 @@
+package com.diguage.algo.leetcode;
+
+public class _0415_AddStrings {
+  // tag::answer[]
+
+  /**
+   * @author D瓜哥 · https://www.diguage.com
+   * @since 2024-09-20 22:18:41
+   */
+  public String addStrings(String num1, String num2) {
+    int max = 0, diff = 0;
+    if (num1.length() < num2.length()) {
+      String tmp = num1;
+      num1 = num2;
+      num2 = tmp;
+    }
+    max = num1.length();
+    diff = max - num2.length();
+    int carry = 0;
+    String result = "";
+    for (int i = max - 1; i >= 0; i--) {
+      int n1 = num1.charAt(i) - '0';
+      int n2 = 0;
+      if (i - diff >= 0) {
+        n2 = num2.charAt(i - diff) - '0';
+      }
+      int sum = n1 + n2 + carry;
+      carry = sum / 10;
+      result = (sum % 10) + result;
+    }
+    return carry == 0 ? result : "1" + result;
+  }
+  // end::answer[]
+
+  public static void main(String[] args) {
+    _0415_AddStrings solution = new _0415_AddStrings();
+    String result = solution.addStrings("11", "123");
+    System.out.println(result);
+  }
+}