编辑代码

#include <iostream>
using namespace std;

int n,m,k,ans;
int w[35],a[35];
bool vis[35];

void dfs(int step = 1)
{
    if(step > m)
    {
        ans++;
        return;
    }

    
    for(int i = a[step-1] + 1;i <= n;i++)
    {
        if(vis[i] == 0 )
        {
            if(w[i] + w[a[step - 1]] <= k || step == 1)
            {
            a[step] = i;
            vis[i] = 1;
            dfs(step + 1);
            vis[i] = 0;
            }
        }
    }
}

int main()
{
    
    cin>>n>>m>>k;
    for(int i = 1;i <= n;i++)
        cin>>w[i];
    dfs();
    cout<<ans;
	return 0;
}