How to reverse the position of a nested loop output? - c

Question

I'm a beginner C programmer and a college freshman.
I need a little help here with a test i'm working on here.
I want to make a nested loop that shows a sorted number. Sorta like this:
1
3 2
4 5 6
10 9 8 7
11 12 13 14 15
21 20 19 18 17 16
22 23 24 25 26 27 28
... ... ... and so on, depending the limit of rows you input
I already tried to make a crude trial-and-error test code:
int i;
int j;
int limit;
int number1 = 1;
int number2 = 3;
int spesial = 0;
printf("Input limit : ");
scanf("%d", &limit);
for (i=1;i<=limit;i++)
{
for(j=1;j<=i;j++)
{
if (i%2==0)
{
printf("%d ", number2);
number2--;
}
else
{
printf("%d ", number1);
}
number1++;
}
if (i%2==0)
{
number2=(i*6)-i+(spesial*1);
spesial+=1;
}
printf("\n");
}
I managed to make it sorted to the 7th rows, but the rest are not..
help please...
I want to know if we could actually control the position of the output without sorta crude our way like this.
Also, sorry for my English... I'm not really from an English speaking country and this is my first time posting/question in this site.
Thank you for reading this lengthy question and I hope you have a good day and good night.

Answer 1

https://ideone.com/yCxpHo:
#include <stdio.h>
#include <stdlib.h>
int main(void)
{
int rows;
int i, j;
int n = 0;
printf ("How many rows do you want? ");
if (scanf("%d", & rows) != 1 || rows < 1) return EXIT_FAILURE;
printf ("\n");
for (i = 1; i <= rows; ++ i) {
for (j = 0; j < i; ++ j) {
printf ("%4d", n + (i % 2 == 0 ? i - j : j + 1));
}
printf ("\n");
n = n + i;
}
return EXIT_SUCCESS;
}

Answer 2

It can be more convenient to create another function that will calculate the biggest number of a row (I called it lineMax).
int lineMax(int num){
int cnt=0;
for (int i=1;i<=num;i++)
cnt+=i;
return cnt;
}
void main(){
int i,j,limit;
printf("Input limit : ");
scanf("%d", &limit);
for(i=1;i<=limit;i++){
if(i%2==0){ //right to left
for(j=lineMax(i);j>=lineMax(i-1)+1;j--)
printf("%d ",j);
}
else{ //left to right
for(j=lineMax(i-1)+1;j<=lineMax(i);j++)
printf("%d ",j);
}
printf("\n");
}
}

Answer 3

You are making a lot of special cases with number1, number2 and special. This will not work for bigger numbers.
One way is to calculate count which will give you the value to start from in each loop of j. count += i and then every time print count -j
count = 0;
for (i=1;i<=limit;i++)
{
count += i;
for(j=0;j< i;j++)
{
printf ("%d ",count-j);
}
printf("\n");
}