第一部分:跟着PPT走去看一下流程控制的语句执行规则:

了解规则后去观察下面的代码:运行结果不展示:流程控制的语句语法要自己去领悟的。

七大语句循环

单分支结构： if(boolean类型的条件表达式/数值/boolean类型变量){ 语句块; } 执行的规则：如果if小括号的值为true，程序执行大括号里面的语句块，否则，将结束整个if的分支结构，程序执行if这个结构后面的语句

双分支结构： if(boolean类型的条件表达式/数值/boolean类型变量){ 语句块1; }else{ 语句块2; }

多分支结构： if(boolean类型的条件表达式/数值/boolean类型变量){ 语句块1; }else if(boolean类型的条件表达式/数值/boolean类型变量){ 语句块2; }else if(boolean类型的条件表达式/数值/boolean类型变量){ 语句块3; }else{ 语句块4; }

执行规则：当程序看到if多分支结构时，首先进入if小括号boolean类型的条件表达式的判断，如果为true，程序会执行第一个大括号里面语句块1的所有内容，执行完后会结束整个多分支结构，如果为 false，程序会执行第一个else if小括号boolean类型的条件表达式的判断，如果为TRUE，程序会执行第二个大括号里面语句块2的所有内容，执行完后会结束整个多分支结构，否则，程序会执行第二个else if小括号boolean类型的条件表达式的判断，如果为TRUE，程序会执行第三个大括号里面语句块3的所有内容，执行完后会结束整个多分支结构，否则程序会执行else后面的这个大括号语句块4的所有的内容。

switch结构： switch(数值类型的表达式/数值){ case 数值1:一系列语句1; case 数值2:一系列语句2; case 数值3:一系列语句3; ........... case n:一系列语句n; default: 一系列语句； }

执行规则：当程序看到switch结构时，会用小括号的数值与case后面的数值进行一一的比较，比较是否相等，如果相等，将会执行case后面的所有的一系列语句并且包括 default后面的一系列语句，如果都没有匹配上，那么程序会执行default后面的一系列语句

循环4要素： 1.循环的起点 2.循环要做的事情 3.循环起点到终点的变化 4.循环的终点

while循环： while(循环条件的判断){循环体} 执行规则：

当程序看到while循环是，首先进入循环条件的判断，如果循环条件为TRUE，那么程序进入循环体，执行循环体内所有的语句，直到看到循环的右大括号时，程序再一次进入循环条件的判断，依次执行，直到循环条件为假的时候，整个while循环结束。

package com.Java.Basics1;
public class as {
  public static void main(String[] args) {
        System.out.println("今天是你的回顾期第一天，走进java程序员");
        System.out.println("java程序第一课");
        System.out.println("思考一下3*5用java语言用什么输出呢");
        int a=3;
        int b=5;
        int c=a*b;
        System.out.println("3*5=15"+a*b);
        System.out.println(c);
        System.out.println("================");
        byte aa=123;
        short ba=32564;
        int ca=4578662;
        long da=467896123;
        long ea=aa+ba+ca+da;
        System.out.println(aa);
        System.out.println(ba);
        System.out.println(ca);
        System.out.println(da);
        System.out.println(ea);
        System.out.println(aa/8);
        System.out.println(ba*8);
        System.out.println(ca+45692);
        System.out.println(da-45623);
        System.out.println(ea^45);
        int aaa=13;
        if(aaa>12) {
          System.out.println("I IOVER YOU");
        }
      }
  }

package com.Java.Basics1;
public class ComB {
  public static void main(String[] args) {
    // TODO Auto-generated method stub
    int number1=6;
    int number2=7;
    int number3=34;
    int c=2;
    int v=5;
    boolean result=((c>v)&&(c!=v));
    boolean result1=((c>v)||(c!=v));
    System.out.println(result);
    System.out.println(result1);
    System.out.println((number1>number2));
    System.out.println("===1==");
    System.out.println((number1<number2));
    System.out.println("===2==");
    System.out.println((number1==number3));
    System.out.println("===3==");
    System.out.println((number1!=number2));
    System.out.println("==4===");
    System.out.println((number1>=number2));
    System.out.println("===5==");
    System.out.println((number1<=number2));
  }
}

package com.Java.Basics1;
public class ComD {
  public static void main(String[] args) {
    // TODO Auto-generated method stub
    /*
     * if else 语句
     */
    int math =102;
    int english=120;
    if(math>110) {
      System.out.println("66666");
    }else {
      System.out.println("les go");
    }
    if(english<110) {
      System.out.println("66666");
    }else {
      System.out.println("les go");
    }
    /*
     * if()else....if()else 多分支
     */
    int x=20;
    if(x>30) {
      System.out.println("a>30");
  }else if(x>20) {
    System.out.println("a>20 ||a<10");
  }else if (x>0) {
    System.out.println("a<0");
  }else {
    System.out.println("a>>0");
  }
  /*
   * switch case break default 语句 一
   */
    String str="今朝有酒1";
    switch(str) {
    case "今":
    System.out.println("7");
    break;
    case"朝":
    System.out.println("4");
    break;
    case"有":
    System.out.println("3");
    break;
    case"今朝有酒":
    System.out.println("今朝有酒 今朝有酒");
    break;
    default:
      System.out.println("i donot know");
    }
    /*
     * switch case break default
     */
    int week=7;
    switch (week) {
    case 0:
      System.out.println("1");
      break;
    case 1:
      System.out.println("1");
      break;
    case 2:
      System.out.println("1");
      break;
    case 3:
      System.out.println("1");
      break;
    case 4:
      System.out.println("1");
      break;
    case 5:
      System.out.println("1");
      break;
    case 6:
      System.out.println("1");
      break;
    case 7:
      System.out.println("sunday");
      break;
    default:
      System.out.println("0k not see you");
    }
    /*
     * while()
     */
    int y=1;
    int sum=0;
    while (y<=10) {
      sum=sum+y;
      y++;
    }
    System.out.println("1到10的和"+sum);
}
}

package com.Java.Basics1;
public class ComD {
  public static void main(String[] args) {
    // TODO Auto-generated method stub
    /*
     * if else 语句
     */
    int math =102;
    int english=120;
    if(math>110) {
      System.out.println("66666");
    }else {
      System.out.println("les go");
    }
    if(english<110) {
      System.out.println("66666");
    }else {
      System.out.println("les go");
    }
    /*
     * if()else....if()else 多分支
     */
    int x=20;
    if(x>30) {
      System.out.println("a>30");
  }else if(x>20) {
    System.out.println("a>20 ||a<10");
  }else if (x>0) {
    System.out.println("a<0");
  }else {
    System.out.println("a>>0");
  }
  /*
   * switch case break default 语句 一
   */
    String str="今朝有酒1";
    switch(str) {
    case "今":
    System.out.println("7");
    break;
    case"朝":
    System.out.println("4");
    break;
    case"有":
    System.out.println("3");
    break;
    case"今朝有酒":
    System.out.println("今朝有酒 今朝有酒");
    break;
    default:
      System.out.println("i donot know");
    }
    /*
     * switch case break default
     */
    int week=7;
    switch (week) {
    case 0:
      System.out.println("1");
      break;
    case 1:
      System.out.println("1");
      break;
    case 2:
      System.out.println("1");
      break;
    case 3:
      System.out.println("1");
      break;
    case 4:
      System.out.println("1");
      break;
    case 5:
      System.out.println("1");
      break;
    case 6:
      System.out.println("1");
      break;
    case 7:
      System.out.println("sunday");
      break;
    default:
      System.out.println("0k not see you");
    }
    /*
     * while()
     */
    int y=1;
    int sum=0;
    while (y<=10) {
      sum=sum+y;
      y++;
    }
    System.out.println("1到10的和"+sum);
}
}

package com.Java.Basics1;
public class ComF {
  public static void main(String[] args) {
    /*
     * for语句
     */
    int sum=0;
    for (int i = 0; i < 6; i++) {
      sum=sum+i;
      System.out.println("hellow world");
    }
    System.out.println(sum);
    System.out.println("-==========");
    for (int g = 0; g < 3; g++) {
      for (int h = 0; h < 6; h++) {
        if(h==4) {
          break;
        }
        System.out.println("g="+g+h  + "h="+g);
      }
    }
    for (int k = 0; k <28; k++) {
      if(k%2==0) {
        continue;
      }
      System.out.println(k+"     "+"k%2≠0");
    }
  }
}

package com.eng;
public class Eng4 {
  public static void main (String[]args) {
    //1
    int age=20;
    boolean  result=age>=18?(true):(false);
    System.out.println(age);
    //2 
    class masx{
      {
      int g =2;
      System.out.println(g);
      }
      {
      int g =2;
      System.out.println(g);
      }
      {
        int g =2;
        System.out.println(g);
        }
      {
        int g =2;
        System.out.println(g);
        }
    }
    }
}

package com.eng;
import java.util.Scanner;
public class Eng6 {
  public static void main (String[]args) {
    Scanner sc = new Scanner (System.in);
    System.out.print("请输入你的消费金额：");
    double sMoney = sc.nextDouble();
    if (sMoney<=0) {
      System.out.println("你输入有！！！！！");
    }else if(sMoney<50) {
      System.out.println("换购活动需要50元，谢谢你的参加");
    }else if(sMoney>=50){
      System.out.println("1 满50元， 加2瓶可乐");
      System.out.println("2 满100元 ，加3瓶酸奶");
      System.out.println("3 满100元，有10元面粉");
      System.out.println("4 满200元，30元的喝喝");
      System.out.println("5 满100元， 加5本子");
      System.out.println("6 满300元， 加15个本子算20元");
      System.out.println("0 不换");
      System.out.println("请输入你的序号");
      int a =sc.nextInt();
      if(a>5 ||a<0) {
        System.out.print("你输入有误！如有需要轻重开始");
      }else {
          if(a==6 && sMoney>=200) {
            System.out.println("满300元， 加15本子");
            System.out.println("本次消费总额为："+(sMoney+40));
          }else if(a==5 && sMoney>=100) {
            System.out.println(" 满100元，90元的喝喝");
            System.out.println("本次消费总额为："+(sMoney+45));
          }else if(a==4 && sMoney>=200) {
            System.out.println(" 满200元，30元的喝喝");
            System.out.println("本次消费总额为："+(sMoney+30));
          }else if(a==3 && sMoney>=100) {
            System.out.println(" 满100元，有10元面粉");
            System.out.println("本次消费总额为："+(sMoney+10));
          }else if(a==2 && sMoney>=100) {
            System.out.println(" 满100元 ，加3瓶酸奶");
            System.out.println("本次消费总额为："+(sMoney+19));
          }else if(a==1 && sMoney>=50) {
            System.out.println(" 满50元， 加2瓶可乐");
            System.out.println("本次消费总额为："+(sMoney+4));  
          }else if(a==0 ) {
            System.out.println("欢迎光临！！！");
          }else {
            System.out.println("你没有达到相应金额");
          }
        }
      }
    }
}

package com.eng;
public class Eng7 {
  public static void main(String[] args) {
    // TODO Auto-generated method stub
      for(int i=1;i<=9;++i){
        for(int j=1;j<=i;++j){
          System.out.print(i+"*"+j+"="+i*j+" ");
        }
        System.out.println();
      }
  } 
  }

package com.eng;
public class Eng9 {
  public static void main(String[] args) {
    // TODO Auto-generated method stub
    //1
    int i = 10;
    while(i>=0){
      System.out.println(i);
      --i;
    }
      //2
      for(int a =1;a<=10;a =a+1){
        System.out.println(a);
    }
      //3
      int a = 1;
      while (a<=1000){
        if(a%2==0){
      System.out.println(a);
        }
        a++;
      }
      //4
      int f=1;
      do{
        System.out.println(f);
        ++f;
      }while(f<=100);
      //5
      int h =1;
      int j =1;
      do{
        System.out.println(j);
        j =j+4;
        h++;
      }while(h<=50);
      //6
      int t =1;
      int sum =0;
      do{
        System.out.println(t);
      sum =sum+t;
        ++t;
      }while(t<=100);
      System.out.println(sum);
    }
}

package com.eng;
  import java.util.Scanner;
  public class Eng10 {
    public static void main(String[] args) {
      //1.创建Scanner对象
      Scanner scanner = new Scanner(System.in);
      //2.提示用户输入年份并且获取年份
      System.out.println("请输入年份");
      int year = scanner.nextInt();
      //3.提示用户输入月份并且获取月份
      System.out.println("请输入月份");
      int month = scanner.nextInt();
      //4.提示用户输入日期并且获取日期
      System.out.println("请输入日期");
      int day = scanner.nextInt();
      //请输入时间
      System.out.println("请输入时间");
      int  house =scanner.nextInt();
      //5.定义一个变量去统计一共过了多少天
      int sum = 0;
      switch(month){
      case 12:
        if(month==12){
          sum = sum+day;
        }else{//过满了整月
          sum = sum+31;
        }
      case 11:
        if(month==11){
          sum = sum+day;
        }else{//过满了整月
          sum = sum+30;
        }
      case 10:
        if(month==10){
          sum = sum+day;
        }else{//过满了整月
          sum = sum+31;
        }
      case 9:
        if(month==9){
          sum = sum+day;
        }else{//过满了整月
          sum = sum+30;
        }
      case 8:
        if(month==8){
          sum = sum+day;
        }else{//过满了整月
          sum = sum+31;
        }
      case 7:
        if(month==7){
          sum = sum+day;
        }else{//过满了整月
          sum = sum+31;
        }
      case 6:
        if(month==6){
          sum = sum+day;
        }else{//过满了整月
          sum = sum+30;
        }
      case 5:
        if(month==5){
          sum = sum+day;
        }else{//过满了整月
          sum = sum+31;
        }
      case 4:
        if(month==4){
          sum = sum+day;
        }else{//过满了整月
          sum = sum+30;
        }
      case 3:
        if(month==3){
          sum = sum+day;
        }else{//过满了整月
          sum = sum+31;
        }
      case 2:
        if(month==1){
          sum = sum+day;
        }else{//过满了整月并且要判断是闰年还是平年
          if((year%400==0)||(year%4==0&&year%100!=0)){//闰年
            sum = sum+29;
          }else{//平年
            sum = sum+28;
          }
        }
      case 1:
        if(month==1){
          sum = sum+day;
        }else{//过满了整月
          sum = sum+31;
        }
      }
      int sum1= 0;
      switch(house){
      case 1:
        if(house==1){
          sum1 = sum1+house;
        }else{//过满了整月
          sum1 = 1;
        }
      case 2:
        if(house==2){
          sum1 = sum1+house;
        }else{//过满了整月
          sum1 = sum1+1;
        }
      case 3:
        if(house==3){
          sum1 = sum1+house;
        }else{//过满了整月
          sum1 = sum1+1;
        }
      case 4:
        if(house==4){
          sum1 = sum1+house;
        }else{//过满了整月
          sum1 = sum1+1;
        }
      case 5:
        if(house==5){
          sum1 = sum1+house;
        }else{//过满了整月
          sum1 = sum1+1;
        }
      case 6:
        if(house==6){
          sum1 = sum1+house;
        }else{//过满了整月
          sum1 = sum1+1;
        }
      case 7:
        if(house==7){
          sum1 = sum1+house;
        }else{//过满了整月
          sum1 = sum1+1;
        }
      case 8:
        if(house==8){
          sum1 = sum1+house;
        }else{//过满了整月
          sum1 = sum1+1;
        }
      case 9:
        if(house==9){
          sum1 = sum1+house;
        }else{//过满了整月
          sum1 = sum1+1;
        }
      case 10:
        if(house==10){
          sum1 = sum1+house;
        }else{//过满了整月
          sum1 = sum1+1;
        }
      case 11:
        if(house==11){
          sum1 = sum1+house;
        }else{//过满了整月
          sum1 = sum1+1;
        }
      case 12:
        if(house==12){
          sum1 = sum1+house;
        }else{//过满了整月
          sum1 = sum1+1;
        }
      case 13:
        if(house==13){
          sum1 = sum1+house;
        }else{//过满了整月
          sum1 = sum1+1;
        }
      case 14:
        if(house==14){
          sum1 = sum1+house;
        }else{//过满了整月
          sum1 = sum1+1;
        }
      case 15:
        if(house==15){
          sum1 = sum1+house;
        }else{//过满了整月
          sum1 = sum1+1;
        }
      case 16:
        if(house==16){
          sum1 = sum1+house;
        }else{//过满了整月
          sum1 = sum1+1;
        }
      case 17:
        if(house==17){
          sum1 = sum1+house;
        }else{//过满了整月
          sum1 = sum1+1;
        }
      case 18:
        if(house==18){
          sum1 = sum1+house;
        }else{//过满了整月
          sum1 = sum1+1;
        }
      case 19:
        if(house==19){
          sum1 = sum1+house;
        }else{//过满了整月
          sum1 = sum1+1;
        }
      case 20:
        if(house==20){
          sum1 = sum1+house;
        }else{//过满了整月
          sum1 = sum1+1;
        }
      case 21:
        if(house==21){
          sum1 = sum1+house;
        }else{//过满了整月
          sum1 = sum1+1;
        }
      case 22:
        if(house==22){
          sum1 = sum1+house;
        }else{//过满了整月
          sum1 = sum1+1;
                  }
      case 23:
        if(house==23){
          sum1 = sum1+house;
        }else{//过满了整月
          sum1 = sum1+1;
        }
      case 24:
        if(house==24){
          sum1 = sum1+house;
        }else{//过满了整月
          sum1 = sum1+1;
        }
        System.out.println(year+"年"+month+"月"+day+"日是该年的第"+sum+"天"+"小时的时间"+sum1);
        System.out.println("-------------------------------------------------");
        System.out.println(year+"年"+month+"月"+day+"日是该年的第"+sum+"天"+"时间"+sum1);
        System.out.println(year+"年"+month+"月"+day+"日是该年的第"+sum+"天"+"小时的时间"+sum1);
        System.out.println("-------------------------------------------------");
        System.out.println(year+"年"+month+"月"+day+"日是该年的第"+sum+"天"+"时间"+sum1);
    }
  }
  }