面试-算法01

/*** 打印九九乘法口诀 方法一*/public void chengfa(){for(int i=1;i<=9;i++){int j = 1;while(j<=i){System.out.print(j+"*"+i+"="+i*j+ " ");j++;}System.out.println();}}/*** 打印九九乘法口诀 方法二*/public void chengfa2(){for(int i =1,j =1;j <=9;i++){System.out.print(i+"*"+j+"="+i*j+" ");if(i==j){i=0;j++;System.out.println();}}}/***去除字符串中多余的空格，只保留一个 */public void removeEmptySpace(){String testStr = "I am   happy to   introduce  myself to  you here!";StringBuffer sb = new StringBuffer();boolean flg = false;for(int i=0;i<testStr.length();i++){char cha = testStr.charAt(i);//System.out.println(cha);if(cha == ' '&& flg){sb.append(cha);flg = false;}else if(cha != ' '){flg =true;sb.append(cha);}}System.out.println(sb.toString());}/*** 压缩字符串* Compress :AAABCCf  ==> 3AB2Cf*/public void compressText(String text){int sum =0;StringBuffer sb = new StringBuffer();char tmp ;for(int i=0;i<text.length();i++){char cha = text.charAt(i);tmp = (i>0)?text.charAt(i-1):text.charAt(i);if(tmp == cha){sum ++;if(i ==text.length()-1){sb.append(sum>1?(sum+""+tmp):tmp);}}else{sb.append(sum>1?(sum+""+tmp):tmp);sum = 1;tmp = text.charAt(i);if(i ==text.length()-1){sb.append(tmp);}}}System.out.println("compressText is:"+sb.toString());}