Simple Java Solution
Intuition\n Describe your first thoughts on how to solve this problem. \n\n# Approach\n Describe your approach to solving the problem. \n\n# Complexity\n- Time 
# Intuition\n<!-- Describe your first thoughts on how to solve this problem. -->\n\n# Approach\n<!-- Describe your approach to solving the problem. -->\n\n# Complexity\n- Time complexity:\n<!-- Add your time complexity here, e.g. $$O(n)$$ -->\n\n- Space complexity:\n<!-- Add your space complexity here, e.g. $$O(n)$$ -->\n\n# Code\n```\nclass Solution {\n    public int numberOfBeams(String[] bank) {\n        int total = 0;\n        int prev = 0;\n        for(String row : bank){\n            int curr = 0;\n            for(int i=0; i < row.length(); i++){\n                if(row.charAt(i) == \'1\'){\n                    curr++;\n                }\n            }\n            if(curr > 0){\n                total += (prev * curr);\n                prev = curr;\n            }\n        }\n        return total;\n    }\n}\n```
['Java']