排序数组中查找和为给定值的两个数O（n）

#include<iostream>
using namespace std;

//排序数组中查找和为给定值的两个数，时间复杂度O（n）
bool findTwoNumbersWithSum(int data[],int length,int sum,int &num1,int &num2){
int ahead=0,behind=length-1;
if(behind<1)
return false;
while(ahead<behind){
if(data[ahead]+data[behind]==sum)
{
num1=data[ahead];
num2=data[behind];
return true;
}
else if(data[ahead]+data[behind]<sum)
{
ahead++;
}
else
{
behind--;
}
}
return false;
}
int main(){
int data[]={1,2,3,4,5};
int num1,num2;
findTwoNumbersWithSum(data,5,7,num1,num2);
cout<<num1<<" "<<num2<<" "<<endl;
return 0;
}