s0160

src/s0160_intersection_of_two_linked_lists.cpp

@@ -0,0 +1,33 @@
+#include "s0160_intersection_of_two_linked_lists.hpp"
+
+ListNode *S0160::getIntersectionNode(ListNode *headA, ListNode *headB) {
+  // 获取两个链表的长度
+  int lenA{0};
+  for (ListNode *ptr = headA; ptr != nullptr; ptr = ptr->next) {
+    ++lenA;
+  }
+  int lenB{0};
+  for (ListNode *ptr = headB; ptr != nullptr; ptr = ptr->next) {
+    ++lenB;
+  }
+  // 设置两个指针的起始位置
+  ListNode *ptrA = headA, *ptrB = headB;
+  if (lenA > lenB) {
+    for (int i{0}; i < lenA - lenB; ++i) {
+      ptrA = ptrA->next;
+    }
+  } else if (lenA < lenB) {
+    for (int i{0}; i < lenB - lenA; ++i) {
+      ptrB = ptrB->next;
+    }
+  }
+  // 两个指针开始同时往前
+  while (ptrA != nullptr) {
+    if (ptrA == ptrB) {
+      return ptrA;
+    }
+    ptrA = ptrA->next;
+    ptrB = ptrB->next;
+  }
+  return nullptr;
+}