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1. function1()
·µ»ØÏàͬ闊¶È數×ÖÐÍ×Ö´®. Àý:
function1(“000000”) => “000001”
function1(”0023") => “0024”
function1(“0009”) => “0010”
function1(“000099”) => “000100”
function1(“9”) => “0” //號碼Ñ環ÔÙÓÃ
³Ìʽ½Ó¿Ú:
public static String function1(String num){....}
2. function2()
將數×ÖËÄ捨ÎåÈëÖÁijС數λ, 並·µ»ØÖ¸¶¨Î»數×Ö´®
function2(123.455,2) => 123.46
function2(123.449,2) => 123.45
function2(123.44,3) => 123.440
function2(123.4455,3) => 123.446
function2(123.4499,3) => 123.450
function2(123.9,0) => 124
³Ìʽ½Ó¿Ú:
public static double function2(double value,int decimalPlaces){....}
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import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;
import java.math.RoundingMode;
import java.text.NumberFormat;
public class test {
public String function1(String str){
String rstr="";
int snum = Integer.parseInt(str);
int len =str.length();
snum++;
rstr =String.format("%0"+len+"d",(int)(snum % Math.pow(10,len)));
return rstr;
}
public double function2(double value, int decimalPlaces) {
NumberFormat nf = NumberFormat.getNumberInstance();
nf.setRoundingMode(RoundingMode.HALF_UP); // ËÄÉáÎåÈë
nf.setMax
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