Number Patterns
Number pattern 41 in C
Write a C program to print the given number pattern using for loop. How to print the given triangular number pattern using loop in C programming. Logic to print the given number pattern using C program.
Example
Input
Input N: 5
Output
1 21 123 4321 12345
Required knowledge
Basic C programming, Loop
Logic to print the given number pattern
1 21 123 4321 12345
To get the logic of the pattern have a close look to the pattern for a minute. You might notice following things about the pattern.
1.It contains N rows (where N is the total number of rows to be printed).
2.Each row contains exactly i columns (where i is the current row number).
3.For all odd rows it contains numbers in increasing order from 1 to i. Hence the inner loop formation to print the odd rows will be for(j=1; j<=i; j++).
4.For all even rows it contains numbers in decreasing order from i to 1. The inner loop formation to print the even rows will be for(j=i; j>=1; j--).
Based on the above observations lets code down the solution of the pattern.
Program to print the given number pattern
/** * C program to print the given number pattern */ #include <stdio.h> int main() { int i, j, N; printf("Enter rows: "); scanf("%d", &N); for(i=1; i<=N; i++) { if(i & 1) { // Print numbers for odd row for(j=1; j<=i; j++) { printf("%d", j); } } else { // Print numbers for even row for(j=i; j>=1; j--) { printf("%d", j); } } printf("\n"); } return 0; }
Output
Enter rows: 5
1 21 123 4321 12345