排序+双指针 复杂度 n log n
#include<bits/stdc++.h>
using namespace std;
int main ()
{
int n,i,j,a[100010],sum;
cin>>n>>sum;
for(i=0;i<n;i++)
cin>>a[i];
sort(a,a+n);
i=0;
j=n-1;
while(i<j){
if(a[i]+a[j]>sum)
j--;
if(a[i]+a[j]<sum)
i++;
if(a[i]+a[j]==sum&&a[i]!=a[j]){
cout<<a[i]<<' '<<a[j]<<endl;
break;
}
}
if(i>=j) cout<<"No Solution";
return 0;
}
blablabla