Assume arr2 is declared as a two-dimensional array of integers. Which of the following segments of code successfully calculates
the sum of all elements arr2? A.int sum = 0;for(int j = 0; j < arr2.length; j++){ for(int k = 0; k < arr2[j].length; k++) { sum += arr2[k][j]; }}
B.
int sum = 0;for(int j = arr2.length − 1; j >= 0; j−−){ for(int k = 0; k < arr2[j].length; k++) { sum += arr2[j][k]; }}
C.
int sum = 0;for(int[] m : arr2){ for(int n : m) { sum += n; }}
int sum = 0;for(int[] m : arr2){ for(int n : m) { sum += n; }}
Explanation:
Option A is wrong because it will throw an ArrayIndexOutOfBoundsException during the last iteration of the first and second loop.
the number of accessible element in the first dimension of arr2 is from 0 to arr2.length-1 but the loop specify 0 to arr2.length which will be the first cause of the error
while that of the second dimension specify 0 to arr2[j].length instead of 0 to arr2[j].length-1
Option B is also wrong because the expression j-- will decrement the value of j instead of incrementing it and the second dimension specify 0 to arr2[j].length instead of 0 to arr2[j].length-1 which will also cause an ArrayIndexOutOfBoundsException.
Option C will successfully calculates the sum of all elements arr2.
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