-s his lan ins after rec accep rst new

Probability

鏈接：http://acm.hdu.edu.cn/showproblem.php?pid=2131

Time Limit: 3000/1000 MS (Java/Others) Memory Limit: 32768/32768 K (Java/Others)
Total Submission(s): 8731 Accepted Submission(s): 4228

Problem Description Mickey is interested in probability recently. One day , he played a game which is about probability with mini.First mickey gives a letter and a word to mini.Then mini calculate the probability that the letter appears in the word.For example,give you the letter "a" and the word "apple". the probability of this case is 0.20000. Input The input contains several test cases. Each test case consists of a letter and a word.The length of the word is no longer than 200. Output For each test case, print the probability rounded to five digits after the decimal point. Sample Input a apple c Candy a banana Sample Output 0.20000 0.20000 0.50000

註：

此題是java水題，註意要int與double進行轉換。

import java.math.BigDecimal;
import java.util.Scanner;

import javax.swing.plaf.basic.BasicArrowButton;

public class Main {

    public static void main(String[] args) {
        Scanner inScanner = new Scanner(System.in);
        while(inScanner.hasNext()) {
            String string 
 
= inScanner.next();
            String string2 = inScanner.next();
            string = string.toLowerCase();
            string2 = string2.toLowerCase();
            char c = string.charAt(0);
            int number = 0;
            BigDecimal bigDecimal = BigDecimal.valueOf(0);
            for
 
(int i = 0;i<string2.length();i++) {
                if(string2.charAt(i) == c) {
                    number ++;
                }
            }
            double number1 = number/1.0;  //int和double的轉換。
            double d = number1/string2.length();
            bigDecimal = bigDecimal.add(BigDecimal.valueOf(d).setScale(5,BigDecimal.ROUND_HALF_UP)); //保留5位小數。
            System.out.println(bigDecimal);
        }
    }

}

（JAVA保留小數問題，基礎）Probability hdu2131