给定一个值S，在有序数组中找出两个元素A和B，使 A+B = S.

package com.array7.algorithm;

public class AlgorithmTest {
public static void main(String[] args) {
int[] arr = {2 ,4 ,5 ,8 ,10 ,12 ,13 ,16 ,17,Integer.MAX_VALUE };
int sum = 13;
String result = getSumElements(arr,sum);
System.out.println(result);

int[] arr2 = {-21 ,-20 ,-15 ,-4 ,-1 ,0 , 2, 13 ,16 ,17,Integer.MAX_VALUE };
int sum2 = -13;
result = getSumElements(arr2,sum2);
System.out.println(result);
}

public static String getSumElements(final int[] arr, final int sum) {
if (arr == null || arr.length < 2) {
throw new IllegalArgumentException("参数不合法...");
}

int min = 0;
int max = arr.length - 1;
long tempSum = 0L;
String result = "not found";
while (min < max) {
tempSum = new Long(arr[min]) + new Long(arr[max]);	// 防止数值溢出，保证数据健壮性
if (tempSum > sum) {
max--;
} else if (tempSum < sum) {
min++;
} else {
result = arr[min] + "," + arr[max];
break;
}
}

return result;
}
}