215. Castle Defence — Count the Guards

Easy · Matrix

A castle's defence grid is a 2D list of 0s and 1s. 1 means a guard is posted there. Count the total number of guards.

Examples

Example 1
Input: grid = [[1,0,1],[0,1,0],[1,1,0]]
Output: 5
Explanation: Five 1s in the grid

Constraints

• 1 ≤ rows, cols ≤ 10