所以我正在自学我购买的这本书中的算法,并且我有一个伪代码用于查找数字数组中两个最近元素之间的距离
MinDistance(a[0...n-1])
Input: Array A of numbers
Output: Minimum Distance between two of its elements
dMin <- maximum integer
for i=0 to n-1 do
for j=0 to n-1 do
if i!=j and | A[i] - A[j] | < dMin
dMin = | A[i]-A[j] |
return dMin
然而,我想对这个算法解决方案进行改进。更改已有的内容,或者一起重写。有人可以帮忙吗?
我用Java写了函数和类来测试伪代码?那是对的吗?再次,从效率的角度来看,我怎样才能让它变得更好。
//Scanner library allowing the user to input data
import java.lang.Math.*;
public class ArrayTester{
//algorithm for finding the distance between the two closest elements in an array of numbers
public int MinDistance(int [] ar){
int [] a = ar;
int aSize = a.length;
int dMin = 0;//MaxInt
for(int i=0; i< aSize; i++)
{
for(int j=i+1; j< aSize;j++)
{
dMin = Math.min(dMin, Math.abs( a[i]-a[j] );
}
}
return dMin;
}
//MAIN
public static void main(String[] args){
ArrayTester at = new ArrayTester();
int [] someArray = {9,1,2,3,16};
System.out.println("NOT-OPTIMIZED METHOD");
System.out.println("Array length = "+ someArray.length);
System.out.println("The distance between the two closest elements: " + at.MinDistance(someArray));
} //end MAIN
} //END CLASS
所以我更新了函数以尽量减少调用 Math.abs 两次。我还能做些什么来改进它。如果我用 sort 重写它,它会完全改变我的 for 循环吗?或者它会是相同的,只是理论上运行得更快。
public int MinDistance(int [] ar){
int [] a = ar;
int aSize = a.length;
int dMin = 0;//MaxInt
for(int i=0; i< aSize; i++)
{
for(int j=i+1; j< aSize;j++)
{
dMin = Math.min(dMin, Math.abs( a[i]-a[j] );
}
}
return dMin;
}