Thread: More array advice!

Well from the first page it seems everyone is at that part of the semester with arrays...lol My question is, I understand how the input works, but now I have to understand how the ouput works?

This program asks for a 5 X 5 array. Then prints out the sum for each of the rows, and then the columns.

EX:
Row totals: 12 5 15 12 23
Column totals: 30 34 45 23 12

You guys get the idea..

Code:

#include<stdio.h>

main ()
{
	int a[5][5];
	int sum=0, row=0, col=0, x=0, n=0;

	for ( row = 0; row < 5; row++ ) 
	{
		printf("Enter row %d (5 digits): ", row+1);

		for ( col = 0; col < 5; col++ ) 
		{
			scanf("%d", &a[row][col]);
			sum += a[row][col];
		}
	}

		printf("Row totals: %d \n", sum );
	
return 0;
}

I think I would just need to use more for statements, becasue this code gives me the sum of all the numbers. However I am confused where?

CJ

to make it easier to start of with, i suggest breaking up the program into several loops, not just 1 loop and a nested loop.

first loop would do the input for the array, no summing up.

another 2 loops for summing the rows and summing the columns.

each time u do the sum of one of the rows or columns, print it out and go on to the next one.

i'll just do an example here, and i think u'll beable to work it out from there.

Code:

// assume array is initialised
int total;
int row, col;

for(row = 0; row < 5; row++)
{
	total = 0;
	for(col = 0; col < 5; col++)
	{
		total += array[row][col];
	}
	printf("%d ", total);
}

WOW...I like both of those ways!

And for once I understand both of them...lol

I'm try both and see which one I like better..

However, there is a second part so I will most likely be back!

CJ

Told ya I get confuzed again!

I need to get the lowest quiz score from each of them! My current for statement returns the last quiz entry. I tried putting the printf inside the second 'for' loop, but it just mirrored the numbers back to me.

Code:

 printf("\n");
printf("Lowest score for each quiz: ");
	
                for(col = 0; col < 5; col++)
	{	
		
		for(row = 0; row < 5; row++)
		{
			low = a[row][col];
			
			if ( a[row][col] < a[row][col])
				low = a[row][col];
		}
				printf("%d ", low);
	}

Any tips?

CJ

Code:

for(row = 0; row < 5; row++)
		{
			low = a[row][col]; // don't think this should be here
			
			if ( a[row][col] < a[row][col])
				low = a[row][col];
		}

well first u should initialise low to the highest possible number.

and low should only take the current value if the current value is lower than 'low'

ie

Code:

if(low > current)
      low = current;

Originally posted by Kyro

Code:

for(row = 0; row < 5; row++)
		{
			low = a[row][col]; // don't think this should be here
			
			if ( a[row][col] < a[row][col])
				low = a[row][col];
		}

well first u should initialise low to the highest possible number.

and low should only take the current value if the current value is lower than 'low'

ie

Code:

if(low > current)
      low = current;

I've tried that already and it either gives me zero or the last array of numbers.

take a look at the code below

compare it to the code you've written.

Code:

int main()
{
	int a[5][5] = 
	{
		{1,4,2,7,0},
		{8,5,7,3,6},
		{2,4,1,7,5},
		{9,4,0,2,7},
		{1,5,3,6,3}
	};
	int col, row, low;

	printf("\n");
	printf("Lowest score for each quiz: ");
	
    for(row = 0; row < 5; row++)
	{	
		low = a[row][0];
		
		// col = 1 since low == a[0][col]
		for(col = 1; col < 5; col++)
		{
			
			if ( a[row][col] < low)
				low = a[row][col];
		}
		printf("%d ", low);
	}

	return 0;
}

/*
Output:

Lowest score for each quiz: 0 3 1 0 1
*/

Originally posted by Kyro
take a look at the code below

Code:

int main()
{
	int a[5][5] = 
	{
		{1,4,2,7,0},
		{8,5,7,3,6},
		{2,4,1,7,5},
		{9,4,0,2,7},
		{1,5,3,6,3}
	};
	int col, row, low;

	printf("\n");
	printf("Lowest score for each quiz: ");
	
    for(row = 0; row < 5; row++)
	{	
		low = a[row][0];
		
		// col = 1 since low == a[0][col]
		for(col = 1; col < 5; col++)
		{
		                low = a[0][col];  // This where I had mine and it was messing up!  Where you have it works!
			if ( a[row][col] < low)
				low = a[row][col];
		}
		printf("%d ", low);
	}

	return 0;
}

/*
Output:

Lowest score for each quiz: 0 3 1 0 1
*/

OK...so when you put it in the first for loop it keeps it on the top row correct? Me putting it in the inside for gave a value of zero and since nothing is lower then zero...

CJ