Tree PreOrder

1. tree 2. parent, child 3. 생각을 한 뒤에 풀이 가능 4. 사내에서 그 사람 코드 바로 보기 가능?

#include <stdio.h> #define MAX_NODE_NUM 15 #define MAX_CHILD_NUM 2 typedef struct { int parent; int child[MAX_CHILD_NUM]; } TreeNode; TreeNode tree[MAX_NODE_NUM]; int nodeNum; int edgeNum; int root; void initTree(void) { int i; int j; for (i = 0; i <= nodeNum; i++) { tree[i].parent = -1; for (j = 0; j < MAX_CHILD_NUM; j++) { tree[i].child[j] = -1; } } } void addChild(int parent, int child) { int i; for (i = 0; i < MAX_CHILD_NUM; i++) { if (tree[parent].child[i] == -1) { break; } } tree[parent].child[i] = child; tree[child].parent = parent; } int getRoot(void) { int i; int j; for (i = 1; i <= nodeNum; i++) { if (tree[i].parent == -1) { return i; } } return -1; } void preOrder(int root) { int i; int child; printf("%d ", root); for (i = 0; i < MAX_CHILD_NUM; i++) { child = tree[root].child[i]; if (child != -1) { preOrder(child); } } } int main(void) { freopen("input.txt", "r", stdin); int test_case; int T; int i; int parent; int child; scanf("%d", &T); for (test_case = 1; test_case <= T; ++test_case) { scanf("%d %d", &nodeNum, &edgeNum); initTree(); for (i = 0; i < edgeNum; i++) { scanf("%d %d", &parent, &child); addChild(parent, child); } root = getRoot(); printf("#%d ", test_case); preOrder(root); printf("\n"); } return 0; }