一个小数学知识:java
import java.math.BigInteger; public class Experiment58 { public static int FindNumber(int number){ int i=0; while(Math.pow(10,i)<=number){ i++; } int result=0; for(int j=i;j>=0;j--){ result=result+(int)(number/Math.pow(10,j)); number=(int)(number%Math.pow(10,j)); } return result; } public static void main(String[] args) { int num=0; System.out.println("3的倍数: 分拆位数和num num/3"); for(int i=10;i<110;i++){ if(i%3==0){ System.out.print(i+"\t\t"); num=FindNumber(i); System.out.print(num+"\t\t"); System.out.print(num+" % 3 = "+num%3+"\t"); System.out.println(); } } } }运行结果:
验证:当一个大于10的数的各个位数的和是3的倍数时,则该数也能整除3spa
源代码:code
public class Experiment59
{
public static int FindNumber(int number){
int i=0;
while(Math.pow(10,i)<=number){
i++;
}
int result=0;
for(int j=i;j>=0;j--){
result=result+(int)(number/Math.pow(10,j));
number=(int)(number%Math.pow(10,j));
}
return result;
}
public static void main(String[] args)
{
int k=0;
for(int i=10;i<=200;i++){
k=FindNumber(i);
if(k%3==0){
System.out.print(i+"\t");
System.out.print(k+"\t");
System.out.print(k+" % 3 = "+k%3+"\t");
System.out.print(i+" % 3 = "+i%3+"\t");
System.out.println();
}
}
}
}
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