Add interation.c recursion.c simple_hash.c binary_search_edge.c binary_search_insertion.c in C codes. (#731)

* fix(codes/cpp): Memory leak fix: the space was not freed when pop removed the element.

* fix(codes/cpp): Fix access error when printArray(arr, 0)

* Update PrintUtil.hpp

* fix(codes/c): Fix some errors of cmake build

* feat(codes/c): Add hashing_search.c

* styles(codes/c): Modify function description

* styles(codes/c): Modify binary_search.c code style

* fix(codes/c): Fix the problem in binary_tree_bfs.c and the problem that the memory is not released.

* feat: Add preorder_traversal_i_compact.c

* feat(codes/c): Add head_sort.c

* feat(codes/c): Add bucket_sort.c

* feat(codes/c): Add binary_search_edge.c

* fix(codes/c): Add programs that are not managed by cmake (c code)

* feat(codes/c): Add selection_sort.c

* style(codes/c): Change swap in selection_sort.c to `selectionSort`

* styles(codes/c): Change style.

* fix(codes/c): Fix some formatting errors and temporarily remove backtracking chapters

* fix(codes/c): Fix space_complexity.c build error.

* feat(codes/c): Add array_binary_tree.c

* feat(code/c): Update push_back and pop_back in vector.h

* styles(codes/c): Adjust  format.

* feat(codes/c): Add `interation.c ` `recursion.c` `simple_hash.c` `binary_search_edge.c` `binary_search_insertion.c` in C codes.

---------

Co-authored-by: Yudong Jin <krahets@163.com>

codes/c/chapter_computational_complexity/iteration.c

@@ -0,0 +1,82 @@
+/**
+ * File: iteration.c
+ * Created Time: 2023-09-09
+ * Author: Gonglja (glj0@outlook.com)
+ */
+
+#include "../utils/common.h"
+
+/* for 循环 */
+int forLoop(int n) {
+    int res = 0;
+    // 循环求和 1, 2, ..., n-1, n
+    for (int i = 1; i <= n; ++i) {
+        res += i;
+    }
+    return res;
+}
+
+/* while 循环 */
+int whileLoop(int n) {
+    int res = 0;
+    int i = 1; // 初始化条件变量
+    // 循环求和 1, 2, ..., n-1, n
+    while (i <= n) {
+        res += i;
+        i++; // 更新条件变量
+    }
+    return res;
+}
+
+/* while 循环（两次更新） */
+int whileLoopII(int n) {
+    int res = 0;
+    int i = 1; // 初始化条件变量
+    // 循环求和 1, 4, ...
+    while (i <= n) {
+        res += i;
+        // 更新条件变量
+        i++;
+        i *= 2;
+    }
+    return res;
+}
+
+/* 双层 for 循环 */
+char *nestedForLoop(int n) {
+    // n * n 为对应点数量，"(i, j), " 对应字符串长最大为 6+10*2，加上最后一个空字符 \0 的额外空间
+    int size = n * n * 26 + 1;
+    char *res = malloc(size * sizeof(char));
+
+    // 循环 i = 1, 2, ..., n-1, n
+    for (int i = 1; i <= n; ++i) {
+        // 循环 j = 1, 2, ..., n-1, n
+        for (int j = 1; j <= n; ++j) {
+            char tmp[26];
+            snprintf(tmp, sizeof(tmp), "(%d, %d), ", i, j);
+            strncat(res, tmp, size - strlen(res) - 1);
+        }
+    }
+    return res;
+}
+
+/* Driver Code */
+int main() {
+    int n = 5;
+    int res;
+
+    res = forLoop(n);
+    printf("\nfor 循环的求和结果 res = %d\n", res);
+
+    res = whileLoop(n);
+    printf("\nwhile 循环的求和结果 res = %d\n", res);
+
+    res = whileLoopII(n);
+    printf("\nwhile 循环（两次更新）求和结果 res = %d\n", res);
+
+    char *resStr = nestedForLoop(n);
+    printf("\n双层 for 循环的遍历结果 %s\r\n", resStr);
+    free(resStr);
+
+    return 0;
+}