init commit

2024-03-19 01:05:51 +08:00
commit 199bbf2628
393 changed files with 34883 additions and 0 deletions
--- a/archive/algorithm/leetcode/15.c
+++ b/archive/algorithm/leetcode/15.c
@@ -0,0 +1,160 @@
+#include <stdio.h>
+#include <string.h>
+#include <stdlib.h>
+#include <math.h>
+
+/**
+ * https://leetcode-cn.com/problems/3sum/description/
+ * 三数之和
+ */
+int **threeSum(int *nums, int numsSize, int *returnSize)
+{
+    int **ret = malloc(sizeof(int *) * numsSize); //行
+    int len = numsSize;                           //数组现在的长度
+    for (int i = 0; i < numsSize; i++)
+    {
+        ret[i] = malloc(sizeof(int) * 3);
+        memset(ret[i], 0, sizeof(int) * 3);
+    }
+    *returnSize = 0;
+    //排序
+    int cmp(const void *a, const void *b)
+    {
+        return (*(int *)a - *(int *)b);
+    }
+    qsort(nums, numsSize, sizeof(int), &cmp);
+    //双指针的方法
+    //-4,-1,-1,0,1,2
+    for (int i = 0; i < numsSize - 2; i++)
+    {
+        if (nums[i] > 0) //有序的情况下,为正数是不可能=0的,跳出循环
+        {
+            break;
+        }
+        if (i > 0 && nums[i] == nums[i - 1]) //向前检查数字重复
+            continue;
+        int h = i + 1, w = numsSize - 1, target = -nums[i];
+        //向中间移动
+        while (h < w)
+        {
+            if (nums[h] + nums[w] == target)
+            {
+                //判断内存足够么
+                if (len - 1 < *returnSize)
+                {
+                    ret = realloc(ret, sizeof(int *) * (len + numsSize));
+                    //重新分配内存
+                    len += numsSize;
+                    for (int i = *returnSize; i < len; i++)
+                    {
+                        ret[i] = malloc(sizeof(int) * 3);
+                        memset(ret[i], 0, sizeof(int) * 3);
+                    }
+                }
+                //符合条件
+                ret[*returnSize][0] = nums[i];
+                ret[*returnSize][1] = nums[h];
+                ret[*returnSize][2] = nums[w];
+                *returnSize = *returnSize + 1;
+                //跳过相同的数字
+                while (h < w && nums[h] == nums[h + 1])
+                    h++;
+                while (h < w && nums[w] == nums[w - 1])
+                    w--;
+                h++;
+                w--;
+            }
+            else if (nums[h] + nums[w] < target)
+            {
+                //小一点,就往右移动
+                h++;
+            }
+            else
+            {
+                //大一点
+                w--;
+            }
+        }
+    }
+
+    return ret;
+}
+
+/*
+int cmpfunc(const void * a, const void * b)
+{
+	return (*(int*)a - *(int*)b);
+}
+
+int** threeSum(int* nums, int numsSize, int* returnSize)
+{
+	int front, back;
+	int i = 0;
+	int **result = 0;
+	int s = 0;
+
+	qsort(nums, numsSize, sizeof(int), cmpfunc);
+
+	while (i < numsSize)
+	{
+		int target = -nums[i];
+		if (target < 0)
+		{
+			break;
+		}
+
+		front = i + 1;
+		back = numsSize - 1;
+
+		while (front < back)
+		{
+			int sum = nums[front] + nums[back];
+			if (sum < target)
+			{
+				front++;
+			}
+			else if (sum > target)
+			{
+				back--;
+			}
+			else
+			{
+				s++;
+				result = (int **)realloc(result, sizeof(int *)*s);
+				int *temp = (int *)malloc(sizeof(int) * 3);
+				temp[0] = nums[i];
+				temp[1] = nums[front];
+				temp[2] = nums[back];
+				result[s-1] = temp;
+
+				while (front < back && nums[front] == temp[1])
+				{
+					front++;
+				}
+				while (front < back && nums[back] == temp[2])
+				{
+					back--;
+				}
+			}
+		}
+		while ((i + 1) < numsSize && nums[i] == nums[i + 1])
+		{
+			i++;
+		}
+		i++;
+	}
+
+	//returnSize = (int *)malloc(sizeof(int));
+	*returnSize = s;
+	return result;
+}
+*/
+
+int main()
+{
+    // int a[] = {-7, -4, -6, 6, 4, -6, -9, -10, -7, 5, 3, -1, -5, 8, -1, -2, -8, -1, 5, -3, -5, 4, 2, -5, -4, 4, 7}, size;
+    int a[] = {0, 0, 0, 0}, size;
+    int **ret = threeSum(a, sizeof(a) / sizeof(int), &size);
+    getchar();
+    return 0;
+}