#include <bits/stdc++.h>

#define X first
#define Y second
#define in(a, x) ((a).find(x) != (a).end())

using namespace std;

const int maxn = 1e5;

void NO()
{
    cout << "Impossible";
    exit(0);
}

int main()
{
    ios_base::sync_with_stdio(false);
    cin.tie(nullptr);

    int n, sum = 0;
    cin >> n;
    int ans = 1e9;

    vector <int> c(n), d(n);
    for (int i = 0; i < n; i++) {
        cin >> c[i] >> d[i];
        sum += c[i];
    }

    int l = -3e7, r = 3e7, m;
    while (r - l > 1)
    {
        m = (l + r) / 2;
        int k = m;
        bool flag = false;
        for (int i = 0; i < n; i++)
        {
            if (i == 0)
            {
                if (d[i] == 2 && k >= 1900)
                    flag = true;

                k += c[i];
            }
            else
            {
                if (d[i] == 2 && k >= 1900)
                    flag = true;
                k += c[i];
            }
        }

        if (!flag)
            l = m;
        else
            r = m;
    }
    if (r == 3e7)
    {
        cout << "Infinity";
        return 0;
    }
    int k = l;
    for (int i = 0; i < n; i++)
    {
        if (k < 1900 && d[i] == 1)
            NO();
        if (k >= 1900 && d[i] == 2)
            NO();

        k += c[i];
    }
    cout << k;
    return 14/88;
}