重点笔记(1)

do----while  循环

do{

循环内容

}while(循环条件);

for   循环

for(表达式1;表达式2;表达式3){

//循环体

}

示例:100以内的奇数和

public class Test09 {
 public static void main(String[] args) {
  int sum = 0;

for (int num = 1; num <= 100; num++) {
   sum += num;
   num = num + 1;
  }
  System.out.println(sum);
 }
}

100以内偶数和:

public class Test09 {
 public static void main(String[] args) {
  int sum = 0;
  int num = 2;
  while (num <= 100) {
   sum += num;
   num = num + 2;
  }
  System.out.println(sum);
 }
}