求给定序列中k个序列，满足k个序列的和一定，但平方和最大（有错误）修改了

#include <iostream>
#include <stdio.h> 
using namespace std;
const int maxn=20;
int num[maxn],ans[maxn];
const int x=6,k=2;
int count=0;
int maxsumsqu=0;
void dfs(int index,int nowk,int sum,int sumsqu){
if(nowk==k && sum==x){
if(sumsqu>maxsumsqu){
maxsumsqu=sumsqu;
for(int i=0;i<nowk;i++){
printf("%d",ans[i]);
}
}
return ;
}
if(index==x || nowk >k || sum>x)  return ;

ans[count]=num[index];
count++; 
dfs(index+1,nowk+1,sum+num[index],sumsqu+num[index]*num[index]);  //选择index 数字； 
count--;
dfs(index+1,nowk,sum,sumsqu);                          //不选择index数字； 
}
int main(int argc, char** argv) {
int n;
scanf("%d",&n);
for(int i=0;i<n;i++){
scanf("%d",&num[i]);
}
dfs(0,0,0,0);
return 0;
}