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package Problem46;

import java.lang.reflect.*;

import java.util.ArrayList;

public class Calculate {

* 求1+2+...+n，不能使用乘除法，循环等

* 利用反射找到函数名递归得到

public int teminator(int n)

{

return 0;

}

public int sum(int n) throws IllegalAccessException, IllegalArgumentException, InvocationTargetException

{

ArrayList<Boolean> testArrayList=new ArrayList<Boolean>();

testArrayList.add(false);

testArrayList.add(true);

Method[] sMethods=this.getClass().getMethods();

int index=testArrayList.indexOf(n==0);

return n--+(Integer)sMethods[index].invoke(this, n);

}

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