第三次作业

include <stdio.h>

include <stdlib.h>

// 结构体定义
typedef struct {
int* data; // 整数数据
int size; // 数据长度
int index; // 当前索引
} NestedIterator;

// 辅助函数：递归处理列表
void flattenHelper(int* arr, int size, int* result, int* index) {
for (int i = 0; i < size; i++) {
if (arr[i] >= 0) {
result[(*index)++] = arr[i]; // 如果是整数，则添加到结果中
} else {
flattenHelper(arr + i + 1, arr[i], result, index); // 递归处理列表
i += arr[i]; // 跳过已处理的列表元素
}
}
}

// 主函数：扁平化嵌套列表
int* flatten(int** nestedList, int nestedListSize, int* nestedListColSize, int* returnSize) {
// 计算扁平化后的结果长度
int totalSize = 0;
for (int i = 0; i < nestedListSize; i++) {
totalSize += nestedListColSize[i];
}

// 分配内存空间
int* result = (int*)malloc(totalSize * sizeof(int));
int index = 0;

// 递归处理列表
for (int i = 0; i < nestedListSize; i++) {
    flattenHelper(nestedList[i], nestedListColSize[i], result, &index);
}

*returnSize = totalSize;
return result;

}

int main() {
int nestedList1[] = {1, 2, 3};
int nestedList2[] = {4, 5};
int nestedList3[] = {6};
int* nestedList[] = {nestedList1, nestedList2, nestedList3};
int nestedListSize = 3;
int nestedListColSize[] = {3, 2, 1};

int returnSize = 0;
int* flattenedList = flatten(nestedList, nestedListSize, nestedListColSize, &returnSize);

printf("Flattened List: ");
for (int i = 0; i < returnSize; i++) {
    printf("%d ", flattenedList[i]);
}
printf("\n");

free(flattenedList);

return 0;

}