课堂测试1
输出某个英文文本文件中 26 字母出现的频率，由高到低排列，并显示字母出现的百分比，精确到小数点后面两位。
字母频率 = 这个字母出现的次数 / （所有A-Z，a-z字母出现的总数）
如果两个字母出现的频率一样，那么就按照字典序排列。
package Statistics; import java.io.File; import java.io.BufferedReader; import java.io.FileReader; import java.io.IOException; public class FileOutput { private static int[][] letter=new int[2][52]; public static void main(String[] args) throws IOException { StringBuilder sb = new StringBuilder(); File directory = new File("");//参数为空 String courseFile = directory.getCanonicalPath()+"/Harry Potter and the Sorcerer's Stone.txt"; BufferedReader bf = new BufferedReader(new FileReader(courseFile)); String content = null; while((content = bf.readLine()) != null){ sb.append(content.trim()); } for(int j=0;j<52;j++) { letter[0][j]=j; letter[1][j]=0; } countCracts(sb.toString(), 'a', 'z'); countCracts(sb.toString(), 'A', 'Z'); for(int i=0;i<52;i++) { int max=letter[1][i],idmax=i; for(int j=i+1;j<52;j++) { if(max<letter[1][j]) { max=letter[1][j]; idmax=j; } } int k,t; k=letter[1][i]; letter[1][i]=letter[1][idmax]; letter[1][idmax]=k; t=letter[0][i]; letter[0][i]=letter[0][idmax]; letter[0][idmax]=t; } double m=0; for(int i=0;i<52;i++) { m+=letter[1][i]; } for(int i=0;i<52;i++) { switch(letter[0][i]) { case 0:System.out.print("A:");break; case 1:System.out.print("B:");break; case 2:System.out.print("C:");break; case 3:System.out.print("D:");break; case 4:System.out.print("E:");break; case 5:System.out.print("F:");break; case 6:System.out.print("G:");break; case 7:System.out.print("H:");break; case 8:System.out.print("I:");break; case 9:System.out.print("J:");break; case 10:System.out.print("K:");break; case 11:System.out.print("L:");break; case 12:System.out.print("M:");break; case 13:System.out.print("N:");break; case 14:System.out.print("O:");break; case 15:System.out.print("P:");break; case 16:System.out.print("Q:");break; case 17:System.out.print("R:");break; case 18:System.out.print("S:");break; case 19:System.out.print("T:");break; case 20:System.out.print("U:");break; case 21:System.out.print("V:");break; case 22:System.out.print("W:");break; case 23:System.out.print("X:");break; case 24:System.out.print("Y:");break; case 25:System.out.print("Z:");break; case 26:System.out.print("a:");break; case 27:System.out.print("b:");break; case 28:System.out.print("c:");break; case 29:System.out.print("d:");break; case 30:System.out.print("e:");break; case 31:System.out.print("f:");break; case 32:System.out.print("g:");break; case 33:System.out.print("h:");break; case 34:System.out.print("i:");break; case 35:System.out.print("j:");break; case 36:System.out.print("k:");break; case 37:System.out.print("l:");break; case 38:System.out.print("m:");break; case 39:System.out.print("n:");break; case 40:System.out.print("o:");break; case 41:System.out.print("p:");break; case 42:System.out.print("q:");break; case 43:System.out.print("r:");break; case 44:System.out.print("s:");break; case 45:System.out.print("t:");break; case 46:System.out.print("u:");break; case 47:System.out.print("v:");break; case 48:System.out.print("w:");break; case 49:System.out.print("x:");break; case 50:System.out.print("y:");break; case 51:System.out.print("z:");break; } System.out.println(String.format("%.2f",(double)(letter[1][i]/m*100))+"%"); } } private static void countCracts(String str, char start, char end) { for(char a = start; a <= end; a++){ int cractCount = str.length() - str.replaceAll(String.valueOf(a), "").length(); if(a>='A'&&a<='Z') { int m=(int)(a-'A'+1); switch(m) { case 1:letter[1][0]=cractCount;break; case 2:letter[1][1]=cractCount;break; case 3:letter[1][2]=cractCount;break; case 4:letter[1][3]=cractCount;break; case 5:letter[1][4]=cractCount;break; case 6:letter[1][5]=cractCount;break; case 7:letter[1][6]=cractCount;break; case 8:letter[1][7]=cractCount;break; case 9:letter[1][8]=cractCount;break; case 10:letter[1][9]=cractCount;break; case 11:letter[1][10]=cractCount;break; case 12:letter[1][11]=cractCount;break; case 13:letter[1][12]=cractCount;break; case 14:letter[1][13]=cractCount;break; case 15:letter[1][14]=cractCount;break; case 16:letter[1][15]=cractCount;break; case 17:letter[1][16]=cractCount;break; case 18:letter[1][17]=cractCount;break; case 19:letter[1][18]=cractCount;break; case 20:letter[1][19]=cractCount;break; case 21:letter[1][20]=cractCount;break; case 22:letter[1][21]=cractCount;break; case 23:letter[1][22]=cractCount;break; case 24:letter[1][23]=cractCount;break; case 25:letter[1][24]=cractCount;break; case 26:letter[1][25]=cractCount;break; } } if(a>='a'&&a<='z') { int m=(int)(a-'a'+1); switch(m) { case 1:letter[1][26]=cractCount;break; case 2:letter[1][27]=cractCount;break; case 3:letter[1][28]=cractCount;break; case 4:letter[1][29]=cractCount;break; case 5:letter[1][30]=cractCount;break; case 6:letter[1][31]=cractCount;break; case 7:letter[1][32]=cractCount;break; case 8:letter[1][33]=cractCount;break; case 9:letter[1][34]=cractCount;break; case 10:letter[1][35]=cractCount;break; case 11:letter[1][36]=cractCount;break; case 12:letter[1][37]=cractCount;break; case 13:letter[1][38]=cractCount;break; case 14:letter[1][39]=cractCount;break; case 15:letter[1][40]=cractCount;break; case 16:letter[1][41]=cractCount;break; case 17:letter[1][42]=cractCount;break; case 18:letter[1][43]=cractCount;break; case 19:letter[1][44]=cractCount;break; case 20:letter[1][45]=cractCount;break; case 21:letter[1][46]=cractCount;break; case 22:letter[1][47]=cractCount;break; case 23:letter[1][48]=cractCount;break; case 24:letter[1][49]=cractCount;break; case 25:letter[1][50]=cractCount;break; case 26:letter[1][51]=cractCount;break; } } } } }优质内容筛选与推荐>>
1、qml 设置tooltip，Customizing ToolTip
2、第04组 Beta冲刺（3/4）
3、[BZOJ]1297: [SCOI2009]迷路
4、GCD学习
5、Java可变参数传递中可以接收多个对象