mirror of
https://github.com/krahets/hello-algo.git
synced 2024-12-25 23:46:29 +08:00
e720aa2d24
* Sync recent changes to the revised Word. * Revised the preface chapter * Revised the introduction chapter * Revised the computation complexity chapter * Revised the chapter data structure * Revised the chapter array and linked list * Revised the chapter stack and queue * Revised the chapter hashing * Revised the chapter tree * Revised the chapter heap * Revised the chapter graph * Revised the chapter searching * Reivised the sorting chapter * Revised the divide and conquer chapter * Revised the chapter backtacking * Revised the DP chapter * Revised the greedy chapter * Revised the appendix chapter * Revised the preface chapter doubly * Revised the figures
76 lines
1.9 KiB
Java
76 lines
1.9 KiB
Java
/**
|
|
* File: iteration.java
|
|
* Created Time: 2023-08-24
|
|
* Author: Krahets (krahets@163.com)
|
|
*/
|
|
|
|
package chapter_computational_complexity;
|
|
|
|
public class iteration {
|
|
/* for 循环 */
|
|
static 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 */
|
|
static 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) */
|
|
static int whileLoopII(int n) {
|
|
int res = 0;
|
|
int i = 1; // 初始化条件变量
|
|
// 循环求和 1, 4, 10, ...
|
|
while (i <= n) {
|
|
res += i;
|
|
// 更新条件变量
|
|
i++;
|
|
i *= 2;
|
|
}
|
|
return res;
|
|
}
|
|
|
|
/* 双层 for 循环 */
|
|
static String nestedForLoop(int n) {
|
|
StringBuilder res = new StringBuilder();
|
|
// 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++) {
|
|
res.append("(" + i + ", " + j + "), ");
|
|
}
|
|
}
|
|
return res.toString();
|
|
}
|
|
|
|
/* Driver Code */
|
|
public static void main(String[] args) {
|
|
int n = 5;
|
|
int res;
|
|
|
|
res = forLoop(n);
|
|
System.out.println("\nfor 循环的求和结果 res = " + res);
|
|
|
|
res = whileLoop(n);
|
|
System.out.println("\nwhile 循环的求和结果 res = " + res);
|
|
|
|
res = whileLoopII(n);
|
|
System.out.println("\nwhile 循环(两次更新)求和结果 res = " + res);
|
|
|
|
String resStr = nestedForLoop(n);
|
|
System.out.println("\n双层 for 循环的遍历结果 " + resStr);
|
|
}
|
|
}
|