[Solved] How would you modify this code to sum all elements in a 2D array?int[][] matrix = {{1,2}, {3}}; int sum = 0; // Your code here | Java

Java - Arrays

How would you modify this code to sum all elements in a 2D array?

int[][] matrix = {{1,2}, {3}};
int sum = 0;
// Your code here

Afor(int i = 0; i <= matrix.length; i++) { for(int j = 0; j < matrix.length; j++) { sum += matrix[i][j]; } }

Bfor(int i = 0; i < matrix.length; i++) { for(int j = 0; j < matrix[i].length; j++) { sum += matrix[i][j]; } }

Cfor(int i = 0; i < matrix.length; i++) { sum += matrix[i]; }

Dfor(int i = 0; i < matrix.length; i++) { for(int j = 0; j < matrix.length; j++) { sum += matrix[j][i]; } }

Step-by-Step Solution

Solution:

Step 1: Use nested loops for 2D array traversal
Outer loop runs over rows, inner loop over columns of each row.
Step 2: Add each element to sum
Access element at matrix[i][j] and add to sum inside inner loop.
Final Answer:
for(int i = 0; i < matrix.length; i++) { for(int j = 0; j < matrix[i].length; j++) { sum += matrix[i][j]; } } -> Option B
Quick Check:
Nested loops with correct bounds sum all elements [OK]

Quick Trick: Use nested loops for 2D arrays [OK]

Common Mistakes:

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