1
21
321
4321
54321
/**
* C program to print number pattern
*/
#include <stdio.h>
int main()
{
int i, j, N;
printf("Enter N: ");
scanf("%d", &N);
for(i=1; i<=N; i++)
{
// Logic to print spaces
for(j=1; j<=N-i; j++)
{
printf(" ");
}
// Logic to print numbers
for(j=i; j>=1; j--)
{
printf("%d", j);
}
printf("\n");
}
return 0;
} 1
21
321
4321
54321
1 21 321 4321 54321
Logic of the above pattern is simple and similar to the previous number pattern that we just printed. In this pattern we only need to add logic of printing extra trailing spaces before the number gets printed. You can hover on to the pattern to see or count total spaces printed per row. The total number of spaces printed per row is N - i (where N is the total number of rows to be printed and i is the current row number).
Step-by-step descriptive logic of the printing spaces:
Finally you are done, lets now implement this on code.
First read the algorithm, then study the program code line by line. After that, compare the code with the output and finally go through the explanation. This approach helps learners understand both the logic and the implementation properly.
After understanding this example, try to rewrite the same program without looking at the code. Then change some values or logic and run it again. This helps improve confidence and keeps learners engaged on the page for longer.