#include <iostream>
using namespace std;
int main(void)
{
int arr[10][10];
int n = 0;
int m = 0;
cin >> n >> m;
int sum = 0;
for (int i = 0; i < m; i++)
{
for (int j = 0; j < n; j++)
{
cin >> arr[i][j];
if (arr[i][j] > 0)
sum += arr[i][j];
}
}
cout << sum << endl;
return 0;
}
using namespace std;
int main(void)
{
int arr[10][10];
int n = 0;
int m = 0;
cin >> n >> m;
int sum = 0;
for (int i = 0; i < m; i++)
{
for (int j = 0; j < n; j++)
{
cin >> arr[i][j];
if (arr[i][j] > 0)
sum += arr[i][j];
}
}
cout << sum << endl;
return 0;
}