java有几种循环-Java中几种常见的循环

java有⼏种循环_Java中⼏种常见的循环多重if_else:packagecom.dengchaoqun.ht;publicclassDouble_For02{/****打印乘法表*/publicstaticvoidmain(String[]args){for(inti=1;i<10;i++){for(intj=1;j<=i;j++){inta=i*j;System.out.print(i+"*"+j+"="+a+"\t");}System.out.println();}}}switch_case:packagecom.dengchaoqun.ht;importjava.util.Scanner;publicclassLeap_yearOrCommon_year{publicstaticvoidmain(String[]args){Scannerscan=newScanner(System.in);intyear;intmonth;//⽤来输⼊⽉份System.out.println("请输⼊年份：");year=scan.nextInt();System.out.println("请输⼊⽉份：");month=scan.nextInt();//判断是否为闰年if((year%4==0&&year%100!=0)||(year%400==0)){System.out.println(year+"年是闰年！");}else{System.out.println(year+"年是平年！");}//输出⽉份的天数switch(month)//switch-case语句输出⽉份的天数{case1:case3:case5:case7:case8:case10:case12:System.out.println(year+"年"+month+"⽉是31天！");break;//判断是否是闰年的⼆⽉还是平年的⼆⽉case2:if((year%4==0&&year%100!=0)||(year%400==0)){System.out.println(year+"年"+month+"⽉是29天！");break;}else{System.out.println(year+"年"+month+"⽉是28天！");break;}case4:case6:case9:case11:System.out.println(year+"年"+month+"⽉是30天！");break;default:System.out.println("请输⼊正确的年份和⽉份！");}scan.close();}}while:packagecom.dengchaoqun.ht;publicclassWhile{/****使⽤while单循环求1！+2！+(7)*/publicstaticvoidmain(String[]args){//TODO⾃动⽣成的⽅法存根inti=1;intj=1;intsum=0;while(i<8){j=i*j;sum+=j;i++;}System.out.println("1！+2！+...+7！="+sum);}}do_while:packagecom.dengchaoqun.ht;importjava.util.Scanner;publicclassDo_while_02{publicstaticvoidmain(String[]args){//TODO⾃动⽣成的⽅法存根Scannerscan=newScanner(System.in);do{intn=0;System.out.println("1.注册");System.out.println("2.登录");System.out.println("0.退出");System.out.println("请选择输⼊项：");n=scan.nextInt();if(n==0){System.out.println("您选择了退出");break;}elseif(n==1){System.out.println("您选择了登录");}elseif(n==2){System.out.println("您选择了退出");}else{System.out.println("您选择了错误");}}while(true);scan.close();}}for:packagecom.dengchaoqun.ht;publicclassDouble_For02{/****打印乘法表*/publicstaticvoidmain(String[]args){for(inti=1;i<10;i++){for(i