public class onepunchman {
  static int r;
  static int[] x;
  static int[] a;

  public static void main(String[] args) {
    Scanner sc = new Scanner(System.in);
    int tc = sc.nextInt();
    sc.nextLine();
    for (int i = 0; i < tc; i++) {
      int n = sc.nextInt();
      r = sc.nextInt();
      int k = sc.nextInt();
      sc.nextLine();
      x = new int[n];
      a = new int[n];
      int total = 0;
      for (int j = 0; j < n; j++) {
        x[j] = sc.nextInt();
        total += sc.nextInt();
        a[j] = total;
        sc.nextLine();
      }
      states = new int[n][k + 1];
      for (int j = 0; j < n; j++) {
        for (int h = 0; h <= k; h++) {
          states[j][h] = -1;
        }
      }
      for (int j = n - 1; j >= 0; j--) {
        for (int q = 0; q <= k; q++) {
          dp(j, q);
        }
      }
      System.out.println(dp(0, k));
    }
  }

  static int[][] states;

  static int dp(int i, int k) {
    if (i == x.length) {
      return 0;
    } else {
      if (states[i][k] == -1) {
        int value;

        if (k > 0) {
          int low = i;
          int high = x.length - 1;
          int max = r * 2 + x[i];
          int j = i;

          while (high >= low) {
            int middle = (low + high) / 2;
            if (x[middle] <= max) {
              low = middle + 1;
              j = middle;
            }
            if (x[middle] > max) {
              high = middle - 1;
            }
          }
          int s;
          if (i > 0) {
            s = a[j] - a[i - 1];
          } else {
            s = a[j];
          }
          value = Math.max(dp(i + 1, k), dp(j + 1, k - 1) + s);
        } else {
          value = dp(i + 1, k);
        }

        states[i][k] = value;
        return value;
      } else {
        return states[i][k];
      }
    }
  }

}