写了一个红黑树，怎么验证算法的准确呢？
首先要找一个正确的，就从网上下载了开源的内核实现。
定义两个宏N和M，N指定单次插入、删除的次数。M表示重复测试的次数。
单次测试：
生成N个node，并且node的值是随机的，插入这个N个数，然后随机删除这N个节点，每次插入和删除都和内核的比较。如果不同则表示错误。
比较算法是：根节点相同，节点值相同、颜色相同、父亲相同、儿子相同。有任何一个不同则失败。
最后使用gcov查看代码覆盖率。
测试代码如下：
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 | #include <stdio.h>#include <stdlib.h>#include "../rbtree.h"#include <string.h>#define N 200#define M 1000struct rb_tree tree;struct rb_node2{ unsigned long rb_parent_color; struct rb_node *right; struct rb_node *left;};struct my_node { struct rb_node node; int v;};struct kernel_node{ struct rb_node2 node; int v;};int cmp(struct rb_node *l, struct rb_node *r){ return ((struct my_node *)r)->v - ((struct my_node *)l)->v;}struct my_node my_nodes[N];struct kernel_node kernel_nodes[N];int val[N];int del[N];void kernel_init();int kernel_insert(struct kernel_node *data);void kernel_del(struct kernel_node *data);struct kernel_node *kernel_root();#define kernel_parent(r) ((struct kernel_node *)((r)->rb_parent_color & ~3))int check(int n){ int i; int ret = 0; int my = 0, k = 0; printf("======================\n"); if (tree.root) my = ((struct my_node *)tree.root)->v; if (kernel_root()) k = kernel_root()->v; printf("my root %d\n", my); printf("kn root %d\n", k); if (my != k) ret = -1; for (i = 0; i < n; i++) { int ml = 0, mr = 0, kl = 0, kr = 0; int mp = 0, kp = 0; int my_color = my_nodes[i].node.color; int kn_color = 1 - (kernel_nodes[i].node.rb_parent_color & 1); if (my_nodes[i].v == 0 && kernel_nodes[i].v == 0) continue; printf("===\n"); if (my_nodes[i].node.parent) mp = ((struct my_node *)(my_nodes[i].node.parent))->v; if (my_nodes[i].node.left) ml = ((struct my_node *)(my_nodes[i].node.left))->v; if (my_nodes[i].node.right) mr = ((struct my_node *)(my_nodes[i].node.right))->v; printf("my node %d, p %d left %d right %d red %d\n", my_nodes[i].v, mp, ml, mr, my_color); if (kernel_parent(&kernel_nodes[i].node)) kp = kernel_parent(&kernel_nodes[i].node)->v; if (kernel_nodes[i].node.left) kl = ((struct kernel_node *)(kernel_nodes[i].node.left))->v; if (kernel_nodes[i].node.right) kr = ((struct kernel_node *)(kernel_nodes[i].node.right))->v; printf("kn node %d, p %d left %d right %d red %d\n", kernel_nodes[i].v, kp, kl, kr, kn_color); if (ml != kl || mr != kr || my_color != kn_color || mp != kp) { fprintf(stderr, "\tdiffer\n"); ret = -1; } } return ret;}int main(){ int n = 0; int i; int ret; while (n++ < M) { n++; fprintf(stderr, "run %d times\n", n); for (i = 0; i < N; i++) { val[i] = i + 1; del[i] = i; } for (i = 0; i < N; i++) { int a = rand() % N, b = rand() % N; int c = val[a], d = val[b]; val[a] = d; val[b] = c; } for (i = 0; i < N; i++) { int a = rand() % N, b = rand() % N; int c = del[a], d = del[b]; del[a] = d; del[b] = c; } memset(my_nodes, 0, sizeof(my_nodes)); memset(kernel_nodes, 0, sizeof(kernel_nodes)); for (i = 0; i < N; i++) { my_nodes[i].v = val[i]; kernel_nodes[i].v = val[i]; } rb_init(&tree, cmp); kernel_init(); for (i = 0; i < N; i++) { ret = kernel_insert(&kernel_nodes[i]); ret = rb_insert(&tree, &my_nodes[i].node); if (ret != 1) fprintf(stderr, "insert failed\n"); ret = check(i+1); if (ret < 0) { fprintf(stderr, "check %d failed\n", i+1); return 1; } } for (i = 0; i < N; i++) { int j = del[i]; printf("del %d\n", my_nodes[j].v); rb_delete(&tree, &my_nodes[j].node); my_nodes[j].v = 0; kernel_del(&kernel_nodes[j]); kernel_nodes[j].v = 0; ret = check(N); if (ret < 0) { fprintf(stderr, "check failed\n"); return 1; } } } fprintf(stderr, "passed\n"); return 0;} |