Handwritten Homework Sheet on Wooden Desk

A realistic smartphone photo of an open lined notebook page resting on a medium-brown wooden desk, capturing a handwritten computer science data structures homework assignment submitted for class. Shot from directly above at a slight angle in a 3:4 vertical framing, with realistic phone-camera perspective, mild paper curvature, and soft warm indoor desk lighting casting subtle shadows. The off-white notebook paper has pale gray horizontal ruled lines, rounded corners, and a glimpse of the previous page along the left edge. Resting beside the notebook on the right is a black transparent-barrel gel pen near the bottom edge, and a small white eraser with gray graphite smudges and a few tiny eraser shavings near the top right corner. The content is handwritten in believable, slightly casual black gel pen Chinese characters, math symbols, and C-style pseudocode with natural spacing, imperfect alignment with the ruled lines, and occasional slant variation: Centered at the top as the header: "[第五章答案]" Section 1: "1. (1) 叶结点数 = (k-1)m + 1。" "(2) 最多结点数 = (k^h - 1)/(k - 1)，最少结点数 = k(h-1)+1。" Section 2: "2. WPL：遍历二叉树，遇到叶子就加 weight × depth，" "根深度为 0。" "代码大意:" Indented beneath: "if(root == NULL) return 0;" "if(!root->left && !root->right)" "return root->weight * depth;" "return WPL(root->left, depth+1) +" "WPL(root->right, depth+1);" Section 3: "3. 二叉树根为 A，左子树 B-D-E-H," "右子树 C-F，其中 F下有 I、G，I下有 M," "M下有 K，G下有 J，J下有 L。" "森林按左孩子右兄弟关系转换即可。" Style: Natural amateur smartphone snapshot, photorealistic desk setting, authentic student handwriting, no digital fonts, no stamps, no watermarks.