## Star Full Diamond

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### Description

Star Full Diamond

For printing the pattern, the number of lines is taken as input. The pattern is divided into two parts. In the first half, the number of stars are increased and in the 2nd part, the number of stars are decreased. Two extra variables are taken here to count the number of stars and the number of spaces for each line. for printing this pattern the number of lines should be odd. So after taking the number of lines as input checking is done. If it is odd, then only the pattern can be printed else an error message is shown.

### Algorithm

``````INPUT: number of lines
OUTPUT: the aforesaid pattern
PROCESS:
Step 1: [taking the input]
Read n [number of lines]
Step 2: [printing the pattern]
Set st<-1
Set sp<-n/2+1
If n mod 2≠0 then
For i=1 to n/2+1 repeat
For j=1 to sp repeat
Print " "
[End of ‘for’ loop]
For k=1 to st repeat
Print "*"
[End of ‘for’ loop]
Move to the next line
Set sp<-sp-1
Set st<-st+2
[End of ‘for’ loop]
Set sp<-sp+2
Set st<-st-4
For i=n/2+2 to n repeat
For j=1 to sp repeat
Print " "
[End of ‘for’ loop]
For k=1 to st repeat
Print "*"
[End of ‘for’ loop]
Move to the next line
Set sp<-sp+1
Set st<-st-2
[End of ‘for’ loop]
else
print “Please give correct input(no. of lines should be odd)"
[End of ‘if]
Step3: Stop.
``````

## Time Complexity:

for(i=1;i<=n/2+1;i++)------------------------ n/2+1

{               for(j=1;j<=sp;j++)-------------------- sp

printf(" ");

for(k=1;k<=st;k++)--------------------st

printf("*");

printf("\n");

sp--;

st+=2;         }

//printing the second half of the pattern where the number of stars

//are decreasing

sp=sp+2;

st=st-4;

for(i=n/2+2;i<=n;i++)-------------------------- n/2

{               for(j=1;j<=sp;j++)------------------ sp

printf(" ");

for(k=1;k<=st;k++)------------------ st

printf("*");

printf("\n");

sp++;

st-=2;     }

}

The time complexity of this program=O((n/2+1)*(sp+st)+ (n/2)*(sp+st))=O($\sqrt{\mathrm{n}}$).