//十六进制数转二进制数importjava.util.Scanner;publicclassH_to_B{staticvoidHtoB_fun(Stringn){char[]ch=n.toCharArray();charstr;Strings="";intp=0;for(inti=0;i='0'&&str<='9'){Stringst=Character.toString(str);//字符转字符串p=Integer.valueOf(st).intValue();//字符串转整型}else{if(str=='A'){str=10;}if(str=='B'){str=11;}if(str=='C'){str=12;}if(str=='D'){str=13;}if(str=='E'){str=14;}if(str=='F'){str=15;}if(str=='.'){str=16;}p=(int)str;}switch(p){case0:s+="0000";break;case1:s+="0001";break;case2:s+="0010";break;case3:s+="0011";break;case4:s+="0100";break;case5:s+="0101";break;case6:s+="0110";break;case7:s+="0111";break;case8:s+="1000";break;case9:s+="1001";break;case10:s+="1010";break;case11:s+="1011";break;case12:s+="1100";break;case13:s+="1101";break;case14:s+="1110";break;case15:s+="1111";break;case16:s+=".";break;default:System.out.println("error!");break;}}System.out.println("结果为二进制：");System.out.println(s);}publicstaticvoidmain(String[]args){Scannersc=newScanner(System.in);System.out.println("请输入16进制数：");Stringstr=sc.nextLine();HtoB_fun(str);}}//二进制数转十六进制数importjava.util.Scanner;publicclassB_to_H{staticvoidBtoH_fun(Stringstr){Strings="";//s用来接收每位十六进制数的位数intchushihua=0;//判断是否有小数点intwest=0,wei=0;//小数点的位置intc;char[]ch1=str.toCharArray();for(inti=0;i=10){switch(c){case10:s+="A";break;case11:s+="B";break;case12:s+="C";break;case13:s+="D";break;case14:s+="E";break;case15:s+="F";break;}}}}System.out.println("结果为十六进制数："+s);}publicstaticvoidmain(String[]args){longstartTime=System.currentTimeMillis();Scannersc=newScanner(System.in);System.out.println("请输入一串二进制数字：");Stringstr=sc.nextLine();//Stringstr="101001011011111101010001";BtoH_fun(str);longendTime=System.currentTimeMillis();longusedTime=endTime-startTime;System.out.println("程序执行所用时间："+usedTime+"毫秒！");}}
