#include <iostream>
#include <cstdlib>

using namespace std;

int main()
{
    int n,m;
    cin >> n >> m;
    int** data = (int**)calloc(n*m,sizeof(int*));
    for(int i=0; i<n*m; i++)
    {
        data[i] = (int*)calloc(2,sizeof(int));
        cin >> data[i][0] >> data[i][1];
    }
    int start;
    cin >> start;
    int curlay = 0;
    int sum;
    int i = start;
    while(curlay<n)
    {
        int rowindex = curlay*m+start;
        int x = data[rowindex][1];
        sum = (sum+x)%20123;

        int num = 0;
        for(int j=0; j<m; j++)
        {
            if(data[curlay*m+j][0] == 1)
            {
                num++;
            }
        }
        if(x>num)
            x = x%num;
        while(x>0)
        {
            if(data[curlay*m+i][0] == 1)
            {
                x--;
                if(x == 0) break;
            }
            i++;
            if(i>=m) i=0;
        }
        curlay++;
        start = i;
    }
    cout << sum << endl;
    return 0;
}