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MA PHƯƠNG c++ Thu Aug 18, 2011 9:07 pm
El Kun
Super Moderator
MA PHƯƠNG
- Code:
#include <stdio.h>
#include <conio.h>
// func declaration
void matrix( int n );
// main()
int main(void)
{
int n;
// input until it's valid.
do
{
printf("\n Plz input size of matrix [ odd size & n < 20 ]: n = ");
scanf("%d",&n);
if ( n % 2 == 0 ) printf("\n Invalid input value .. Plz re-input ... \n");
}
while ( n % 2 == 0 );
if ( n > 20 ) { n = 19 ; // in case of n is greater than 20
printf("\n %d is greater than 20 & set to be default as 19 .",n ); } // end if
// call matrix()
matrix(n);
// stop to watch
getch();
return 0;
}
// function matrix(int n)
void matrix( int n )
{
int a[20][20];
int i, j, row, col, count = 1;
int old_row, old_col, sum = 0;
// set starting value of array
for ( i = 0 ; i < n ; i++ )
for ( j = 0 ; j < n ; j++ )
a[i][j] = 0;
// set the 1st value to start
row = 0; col = (n-1) / 2;
while ( count < n*n + 1 )
{
a[row][col] = count++ ; // set value for elements
old_row = row ; old_col = col; // save the last addresses
// define whether going out of array
row -= 1; if ( row == -1 ) row = n - 1;
col += 1; if ( col == n ) col = 0;
// in case of already having number
if ( a[row][col] != 0 )
{
row = old_row + 1;
col = old_col;
} // end if
} // end while
// print result
printf("\n");
for ( i = 0 ; i < n ; i++ )
{
for ( j = 0 ; j < n ; j++ )
printf("%4d",a[i][j]);
printf("\n");
} // end for
// calculate sum
for ( j = 0 ; j < n ; j++ )
sum += a[0][j];
printf("\n Sum of each row - column - diagonal line is : %d " , sum);
return;
}
