CF-Making Towers

正确代码：

#include<bits/stdc++.h>
using namespace std;
#define x first
#define y second
const int N = 2e5 + 10;
typedef long long LL;
typedef pair<int, int> PII;
// PII a[N];
int cnt[N];
int main()
{
  int t;
  cin >> t;
   while(t --)
   {
      int n;
      cin >> n;
      vector<int>a[N];
      
      for(int i = 1; i <= n; i  ++){
         int tp;
         cin >> tp;
         a[tp].push_back(i);
          
      }

      for(int i = 1; i <= n; i ++)
      {
        if(a[i].size() == 0){
                cout << 0 <<" ";
                continue;
        }
        else {
          int ans  = 1;
          for(int j = 0; j < a[i].size() - 1; j ++)
          {
            if((a[i][j + 1] - a[i][j] - 1) % 2 == 0 || a[i][j + 1] - a[i][j] == 1)ans ++;
            
          }
          cout << ans << " ";
        }
      }        
       cout << endl;
    }
      
   
}

错误代码：

#include<bits/stdc++.h>
using namespace std;
#define x first
#define y second
const int N = 2e5 + 10;
typedef long long LL;
typedef pair<int, int> PII;
// PII a[N];
int cnt[N];
int main()
{
  int t;
  cin >> t;
   while(t --)
   {
      int n;
      cin >> n;
      vector<int>a[N];
      for(int i = 1; i <= n; i  ++){
         int tp;
         cin >> tp;
         a[tp].push_back(i);
          
      }

      for(int i = 1; i <= n; i ++)
      {
        if(a[i].size() == 0){
                cout << 0 <<" ";
                continue;
        }
        else {
          int ans  = 1;
          for(int j = 0; j < a[i].size() - 1; j ++)
          {
            if((a[i][j + 1] - a[i][j] - 1) % 2 == 0 || a[i][j + 1] - a[i][j] == 1)ans ++;
            
          }
          cout << ans << " ";
        }
      }        
       cout << endl;
    }
      
   
}

定义vector数组比清空vector数组所需要的时间长？