Thread: can't find error(s) in my program..help?

I have to write a program to read this matrix

3 4
1 4 5 4
4 5 6 5
1 2 2 3

I wrote it, and my program is not properly reading it.

Code:

#include <stdio.h>
int
main ()
{

FILE *cap;
	int rowsize, colsize, i, j, x, y, b, c;
	int mat[100][100];
	cap = fopen ("mat1.txt", "r");

	fscanf (cap, "%d", &rowsize);
	fscanf (cap, "%d", &colsize);



	for (i = 0; i < rowsize; ++i)
	{
		for (j = 0; j < colsize; ++j)
		{
			fscanf (cap, "%d", &mat[i][j]);
		}
	}

			
			y = mat[0][0];
			x = mat[rowsize-1][colsize-1];
			mat[0][0]= x;
			mat[rowsize-1][colsize-1] = y;
	
			b = mat[0][colsize-1];
			c = mat[rowsize-1][0];
			mat[0][colsize-1] = c;
			mat[rowsize-1][colsize-1] = b;
		
	
		
		for (j = 1; j < colsize - 2; ++j)
		{
			
			
			mat [rowsize-1][j] = mat[rowsize-1][j] * 2;
			
		}
	  
	 	 
		for (i = 0; i < rowsize; ++i)
		{
			
			if (mat[i][1] % 2 == 0) 
			{
				mat[i][1] = mat[i][1] / 2;
			}
			
			    
		}
	


			for (i = 0; i < rowsize; ++i);
			{
				for (j = 0; j < colsize; ++j)
				{
					printf ("%3d", mat[i][j]);
					printf ("\n");
				}
			}

	fclose (cap);
		
}

What results were you expecting? It looks like you have some parenthesis out of place. Here is the pseudocode of what I think you were trying to do (indentation is used instead of parenthesis).

Code:

#include <stdio.h>
int main  void
	FILE *cap
	int rowsize, colsize, i, j, x, y, b, c
	int mat[100][100]
	cap = fopen  "mat1.txt", "r"
	fscanf  cap, "%d", &rowsize
	fscanf  cap, "%d", &colsize
	
	printf  "read from file: \n%d %d\n", rowsize,colsize
	for  i = 0; i < rowsize; ++i
		for  j = 0; j < colsize; ++j
			fscanf  cap, "%d", &mat[i][j]
			printf  "%d ",mat[i][j]
			y = mat[0][0]
			x = mat[rowsize-1][colsize-1]
			mat[0][0]= x
			mat[rowsize-1][colsize-1] = y
			b = mat[0][colsize-1]
			c = mat[rowsize-1][0]
			mat[0][colsize-1] = c
			mat[rowsize-1][colsize-1] = b
		printf  "\n"
	printf  "\nresult:\n"
		
	for  j = 1; j < colsize - 2; ++j
        mat [rowsize-1][j] = mat[rowsize-1][j] * 2
		for  i = 0; i < rowsize; ++i
			if  mat[i][1] % 2 == 0
				mat[i][1] = mat[i][1] / 2
			for  i = 0; i < rowsize; ++i
				for  j = 0; j < colsize; ++j
					printf  "%3d", mat[i][j]
				printf  "\n"
	fclose  cap
	return 0

Anchor, a free, GPL project I'm working on: Anchor | freshmeat.net will convert the above pseudocode to C and compile it producing this result:

Code:

read from file: 
3 4
1 4 5 4 
4 5 6 5 
1 2 2 3 

result:
  3  2  5  1
  4  5  6  5
  1  4  2  1

This is what Anchor sends to the compiler. Just be sure to tell it if you prefer -tabs.

Code:

#include <stdio.h>
int main (void){
	FILE *cap;
	int rowsize, colsize, i, j, x, y, b, c;
	int mat[100][100];
	cap = fopen ("mat1.txt", "r");
	fscanf (cap, "%d", &rowsize);
	fscanf (cap, "%d", &colsize);
	printf ("read from file: \n%d %d\n", rowsize,colsize);
	for (i = 0; i < rowsize; ++i){
		for (j = 0; j < colsize; ++j){
			fscanf (cap, "%d", &mat[i][j]);
			printf ("%d ",mat[i][j]);
			y = mat[0][0];
			x = mat[rowsize-1][colsize-1];
			mat[0][0]= x;
			mat[rowsize-1][colsize-1] = y;
			b = mat[0][colsize-1];
			c = mat[rowsize-1][0];
			mat[0][colsize-1] = c;
			mat[rowsize-1][colsize-1] = b;
 		}	printf ("\n");
 	}	printf ("\nresult:\n");
	for (j = 1; j < colsize - 2; ++j){
        mat [rowsize-1][j] = mat[rowsize-1][j] * 2;
		for (i = 0; i < rowsize; ++i){
			if (mat[i][1] % 2 == 0){
				mat[i][1] = mat[i][1] / 2;
 			}	for (i = 0; i < rowsize; ++i){
				for (j = 0; j < colsize; ++j){
					printf ("%3d", mat[i][j]);
 				}	printf ("\n");
 	}	}	}	fclose (cap);
	return 0;
}

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