Most of students who doing studies in software engineering
field most probably face FOR LOOP challenges in beginning of their academic
life. I think most of student get trouble, because they try to start coding without
analyzing the problem. In this post I decide to introducing some tips for solve
these kind of problems.
1. Let’s think we have a problem like this.
2. Before we start the coding we should clearly analyzing
the position of the stars and the positions of the spaces. In order to do that
I think better to doing some rough work like this.(You can easily sketch a
draft using word processing software like MS Office.)
Ok Let’s go through the draft.
a.
I think you have some idea about how to create
the basic star triangle, basically we need two for loops to crate
triangle.
i.
Main For Loop
For maintain horizontal view of the
triangle.
ii.
Secondary For Loop(s)
Always inside the Main for
loop, this would be handle the vertical view of the triangle. In basic
level mostly we can see only one secondary for loop, But in the advanced triangle
problem’s like this we should add more than one secondary for loop.
b.
Ok, let’s consider main for loop.
I mention main for loop is always
maintain the horizontal view of the triangle. In this problem also the same. We
can easily define a for loop for handle a height of the triangle.
for(i=1;i<=h;i++)
{
}
c.
Secondary for loop(s)
Let’s consider first row of the
draft.
If you clearly analyze the draft
you can see four major parts of the vertical view of the draft. Those are space(s),
filling cell(s), space(s) & filing cell(s).
When we consider the whole
draft we can easily understand increasing and decreasing of these spaces(s) and
the filing cell(s).
Let’s go through the major parts
of the vertical view.
i.
Space(s) I
This part follow decreasing
pattern (2,1,0). It’s a arithmetic series decreasing values one by one in each
step.
And also I’ll numbering each row
1 to 3, from top to bottom. My target is get the equation of the space(s) and
row numbers.
In 1st row 2 spaces.
In 2nd row 1 spaces.
In 3rd roe 0 spaces.
I think you catch the pattern. In
each row we should print the spaces following this equation.
Height of row – Row Number =
Number of spaces
I’ll put first secondary for
loop for handle this.
for(j=h-i;j>=1;j--)
{
printf("
");
}
ii.
Filing cell(s) / Star(s)
This part follow increasing
pattern (1,3,5). It’s also arithmetic series increasing values two by two in
each step.
I’ll numbering each row 1 to 3,
from top to bottom again. My target is same as the first step. It’s for get the
equation of the filing cell(s) and row numbers.
In 1st row 1 spaces.
In 2nd row 3 spaces.
In 3rd roe 5 spaces.
I think you catch the pattern. In
each row we should print the stars following this equation.
Row Number + Row Number - 1=
Number of stars
I’ll put second secondary for
loop for handle this.
for(k=i+(i-1);k>=1;k--)
{
printf("*");
}
iii.
Space(s) II
This part follow decreasing
pattern (4,2,0). It’s a arithmetic series decreasing values two by two in each
step.
And also I’ll numbering each row
1 to 3, from top to bottom. My target is get the equation of the space(s) and
row numbers.
In 1st row 4 spaces.
In 2nd row 2 spaces.
In 3rd roe 0 spaces.
I think you catch the pattern. In
each row we should print the spaces following this equation.
(Height of row – Row Number) * 2
= Number of spaces
I’ll put first secondary for
loop for handle this.
for(l=(h-i)*2;l>=1;l--)
{
printf("
");
}
iv.
Filing cell(s) / Star(s)
This part follow increasing
pattern (1,3,5). It’s also arithmetic series increasing values two by two in
each step.
I’ll numbering each row 1 to 3,
from top to bottom again. My target is same as the first step. It’s for get the
equation of the filing cell(s) and row numbers.
In 1st row 1 spaces.
In 2nd row 3 spaces.
In 3rd roe 5 spaces.
I think you catch the pattern. In
each row we should print the stars following this equation.
Row Number + Row Number - 1=
Number of stars
I’ll put second secondary for
loop for handle this.
for(k=i+(i-1);k>=1;k--)
{
printf("*");
}
d.
New Line
After each row we should print a
new line(\n). In order to do that we will put a
printf("\n");
code for bottom of the secondary
for loops.
Here’s the final code for this problem.
int main(void)
{
int i=0;
int j=0;
int k=0;
int l=0;
int m=0;
int h=0;
printf("Enter hight of tree: ");
scanf("%d",&h);
for(i=1;i<=h;i++)
{
for(j=h-i;j>=1;j--)
{
printf(" ");
}
for(k=i+(i-1);k>=1;k--)
{
printf("*");
}
for(l=(h-i)*2;l>=1;l--)
{
printf(" ");
}
for(m=i+(i-1);m>=1;m--)
{
printf("*");
}
printf("\n");
}
}
I think you got some idea about how to solve these kind of
problems. Now you can try different pattern by yourself.
Happy Coding……………………
