answer:
- Print graphics must be double loop.
- Each of the above line stars more gradually, following each row gradually less must be 2 cyclic groups, a top tube, a tube below.
- Therefore, the weight for the first four lines loop condition i <(n + 1) / 2 above.
- The first four lines space law: three pairs of first row spaces, the second line of two pairs of spaces, one pair of the third row spaces, no fourth row. 7/2 = 3 and i is from 0 to 3, so think of n / 2 - i.
- The first four lines Star Law: 1 3 5 7, i from 0 to 3, so think of 2 * i + 1
- Here and so on.
method one:
#include <stdio.h>
int main()
{
int n, i, j;
scanf("%d", &n);
for (i = 0; i < (n + 1) / 2; i++)
{ //前四行。
for (j = 0; j < n / 2 - i; j++)
printf(" ");
for (j = 0; j < 2 * i + 1; j++)
printf("* ");
printf("\n");
}
for (i = 1; i <= (n - 1) / 2; i++)
{ //后三行。
for (j = 0; j < i; j++)
printf(" ");
for (j = 0; j < n - 2 * i; j++)
printf("* ");
printf("\n");
}
return 0;
}
Method Two:
#include <stdio.h>
int main()
{
int n, i, j;
scanf("%d", &n);
for (i = 0; i < n / 2 + 1; i++)
{
for (j = 0; j < n / 2 - i; j++)
printf(" ");
for (j = 0; j < (i + 1) * 2 - 1; j++)
printf("* ");
printf("\n");
}
for (i = n / 2; i > 0; i--)
{
for (j = n / 2 - i + 1; j > 0; j--)
printf(" ");
for (j = i * 2 - 1; j > 0; j--)
printf("* ");
printf("\n");
}
return 0;
}
