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public class Test{
public static void main(String args[]){
System.out.println(0.05+0.01);
System.out.println(1.0-0.42);
System.out.println(4.015*100);
System.out.println(123.3/100);
}
};
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0.060000000000000005
0.5800000000000001
401.49999999999994
1.2329999999999999
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public double round(double value){
return Math.round(value*100)/100.0;
}
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4.015*100=401.49999999999994
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java.text.DecimalFormatÒ²²»Äܽâ¾öÕâ¸öÎÊÌ⣺
System.out.println(new java.text.DecimalFormat("0.00").format(4.025));
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BigDecimal
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BigDecimal(double val)
 
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