9每个数字出现的次数并打印出来

输出99乘法口诀表

import java.util.HashMap;import java.util.Iterator;import java.util.Map;import java.util.Map.Entry;import java.util.Set;public class MultiplicationTable {public static void main(String[] args) {// 定义字符串缓存，用来存放乘积结果StringBuffer sb = new StringBuffer();// 输出乘法口诀表for (int i=1; i<=9; i++) {for (int j=1; j<=i; j++) {// 做对齐调整，从第二列开始，若结果长度为个位数，，则在结果前面补空格if (j ==2 && String.valueOf(i*j).length() == 1) {System.out.print(j + "*" + i + "= " + i*j + " ");// 将乘积存放在sb中sb.append(i*j);} else {System.out.print(j + "*" + i + "=" + i*j + " ");sb.append(i*j);}}// 一行结束，进行换行操作System.out.println();}// 定义map，存放字符和其出现的次数Map<Character, Integer> map = new HashMap<Character, Integer>();String str = sb.toString();// 遍历str,将字符及其出现的次数存放入mapfor (int i=0; i<str.length(); i++) {Character num = str.charAt(i);if (null != map.get(num)) {map.put(num, map.get(num) + 1);} else {map.put(num, 1);}}// 获取entry结果集，并遍历输出Set<Entry<Character, Integer>> entrySet = map.entrySet();Iterator<Entry<Character, Integer>> it = entrySet.iterator();while (it.hasNext()) {Entry<Character, Integer> entry = it.next();System.out.println(entry.getKey() + " " + entry.getValue());}}}

没有早一步，也没有晚一步，刚好遇上了你！