include

include

include

include

using namespace std;

const int N = 10010, M = 110, mod = 20123;

int n, m, k; bool st[N][M]; //有无梯子 int x[N][M]; // 提示

int main(){

scanf("%d%d",&n,&m);
for(int i = 0;i<n;i++){
	for(int j=0;j<m;j++) 
		scanf("%d%d",&st[i][j],&x[i][j]); 
}
scanf("%d",&k);
int res = 0;
for(int i=0;i<n;i++){
	int sum = 0;
	for(int j=0;j<m;j++) sum += st[i][j];
	int t = x[i][k];
	t %= sum;
	if(!t) t = sum; 
	
	res = (res + x[i][k]) % mod;
	
	for(int j = k;;j = (j+1) % m){
		if(st[i][j]){
			t--;
			if(t == 0){
				k = j;
				break;
			}
		}
	}
	
}
cout << res ;
return 0;

}