# Thread: 2d Array Sums Help

1. Member
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## 2d Array Sums Help

Well, looks like this my first post. Need a little help with my homework. Anyway, here's what I have so far. Both #'s 2 and 3 are somewhat similar, but I'm stumped. The main method is given by default. Please && Thank you.

Java Code:
```    /* Step 2:  Write a method with the header

public static int sumRow(int[][] arr, int m)

that returns the sum of the elements in row m.
*
Assume the value of m satisfies 0 <= m < arr.length
*/
public static int sumRow(int[][] arr, int m){
int sum = 0;
for (m = 0; m < arr.length; m++){
for (int num = 0; num < arr[m].length; num++){
sum = sum + arr[m][num];

}
}
return sum;
}

/* Step 3:  Write a method with the header

public static int sumCol(int[][] arr, int n)

that returns the sum of the elements in col n

Assume (i) every row contains the same number of columns and (ii)
the value of n satisfies 0 <= n < arr[0].length
*/

/* Suggestion:  Before writing sumRow and sumCol, review the
computeSum method in the notes for Lecture 18.
*/
public static int sumCol(int[][] arr, int n){
int sum = 0;
for (int num = 0; num < n; num++){
for (int num2 = 0; num2 < n; num2++){
sum = sum + arr[num][num2];

}
}
return sum;
}

public static void main(String[] args)
{
final int ROWS = 40;
final int COLS = 15;
Scanner in = new Scanner(System.in);
int[][] data = new int[40][15];
int row;
int col;

for(int j = 0; j < data.length; j++)
for(int k = 0; k < data[j].length; k++)
data[j][k] = (int)( (j + k)*(Math.random() + 1));

System.out.println("Enter an integer from 0 to " + (ROWS - 1));
row = in.nextInt();
System.out.println("Enter an integer from 0 to " + (COLS- 1));
col = in.nextInt();

System.out.println("The sum of the elements in row " + row +
" is " + sumRow(data, row));
System.out.println("The sum of the elements in row " + row +
" is " + sumCol(data, col));
}

}```

2. Member
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3. Member
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## Re: 2d Array Sums Help

Originally Posted by coasterguy10
Aha, now it makes complete sense. Thanks alot man. Seems I was over analyzing the entire thing.

4. Member
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## Re: 2d Array Sums Help

Originally Posted by XxVashxX
Aha, now it makes complete sense. Thanks alot man. Seems I was over analyzing the entire thing.
No problem, glad I could help

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