#include <bits/stdc++.h>
using namespace std;
int main() {
  ios_base::sync_with_stdio(false);
  cin.tie(0);
  cout.tie(0);
  int q;
  cin >> q;
  while (q--) {
    int n;
    cin >> n;
    long long dp[n][3];
    long long a[n], b[n];
    for (int i = 0; i < n; i++) {
      cin >> a[i] >> b[i];
    }
    for (int i = 0; i < n; i++) {
      for (int j = 0; j < 3; j++) {
        dp[i][j] = 2000000000000000000;
      }
    }
    dp[0][0] = 0;
    dp[0][1] = b[0];
    dp[0][2] = 2 * b[0];
    for (long long i = 1; i < n; i++) {
      for (long long j = 0; j < 3; j++) {
        for (long long k = 0; k < 3; k++) {
          if (a[i] + j != a[i - 1] + k) {
            dp[i][j] = min(dp[i][j], dp[i - 1][k] + j * b[i]);
          }
        }
      }
    }
    cout << min(dp[n - 1][0], min(dp[n - 1][1], dp[n - 1][2])) << "\n";
  }
}
