#include <stdio.h>

void Input_Arr(int arr[][11], int x, int y)
{
	for (int i = 0; i < x; i++)
	{
		for (int j = 0; j < y; j++) 
		{
			scanf("%d", &arr[i][j]);
		}
	}
}

int Count_Arr(int arr[][11], int x, int y)
{
	int count_sum = 0; 
	for (int i = 0; i < x; i++)
	{
		for (int j = 0; j < y; j++)
		{
			if (arr[i][j] > 0)
			{
				count_sum += arr[i][j];
			}
		}
	}
	return count_sum;  
}

int main()
{
	int arr[11][11] = { 0 }; 
	int x = 0; 
	int y = 0; 
	scanf("%d %d", &x, &y); 
	Input_Arr(arr, x, y);
	int ret = Count_Arr(arr, x, y);
	printf("%d\n", ret); 
	return 0; 
}