Thread: Help Me For My Homework Program

PLease help of doing a programming for the output is like this

1
232
34543
4567654
567898765
67890109876
7890123210987
890123454321098
90123456765432109
0123456789876543210

this is a pyramid
using a loop...
please help me???

functions f and f1 return the same values , f is going to be very inefficient compared to f1 .
The logic of the pattern is
at the ith row there are 2*i-1 elements , the starting from i%10 , the values are are incremented by 1 (modulo 10) for the first i elements , therafter they are decremented by 1 (modulo 10 adjusted for negative by adding 10 if required) .

#include <stdio.h>

int f(int i,int j)
{
int ans;
if( (i<=0) || (j<=0) ) return -1;
if(j==1) ans=i%10;
else if(j<=i)
ans= (f(i,j-1)+1)%10;
else
{
ans=(f(i,j-1)-1)%10;
if(ans<0) ans +=10;
}
return ans;
}


int f1(int i,int j)
{
int ans;
if( (i<0) || (j<0) ) return -1;
if(j<=i) ans=(i+j-1)%10;
else
{
ans=(2*i-1-(j-i))%10;
if(ans<0) ans +=10;
}
return ans;
}


int main(void)
{
int i,j;
for(i=1;i<=10;i++)
{
for(j=1;j<=2*i-1;j++)
printf("%d",f(i,j));
putchar('\n');
}
return 0;
}

I deleted my previous post because I was a jerk in it. Sorry. Hey pinko they way you took was much harder then nessary. I did it using 3 variables, and a total of 3 for loops.

Paul to do this pyramids you have to look at the different elements. In this one I found 3 main parts. 1 is the center number, 2 is the outside numbers, and 3 is the number in between.

First the center number. I called this value X. X is increasing by 2 on every line but displaying only the last digit. X increase to a max of 19. A simple loop for that is here: for(x=1;x<20;x+=2).

The second one is the outside numbers. I called this value Z. Z is increasing by 1 on every line. Now I didn't use a for loop on this. I just increased it by 1 on every X loop.

The third is the numbers between Z and X. I called this value Y. Now Y is used two for loops on. One for the values between Z and X, and the second for the values between X and the second Z.

Now that I've explained how to do it you should be able to read the code and understand how to do them in the future.

Code:

int main(void)
{
int x,y,z=0;
for(x=1;x<20;x+=2)
     {
     for(y=z+1;y<x;y++)
          printf("%d",y%10);

     printf("%d",x%10);

     for(y=x-1;y>z;y--)
          printf("%d",y%10);

     printf("\n");
     z++;
     }
}

Oh yeah? Top this (using a loop)!

Code:

#include <stdio.h>
int main( void )
{
   char *data[10] = {
   "         1", 
   "        232" ,
   "       34543" ,
   "      4567654" ,
   "     567898765" ,
   "    67890109876" ,
   "   7890123210987" ,
   "  890123454321098" ,
   " 90123456765432109" ,
   "0123456789876543210"};
   int x;
   for(x=0;x<10;x++)
   puts(data[x]);
   return 0;
}

Quzah.

I dont think whether one can claim that a particular program is more efficient just by counting the number of variables and loops , for example this program which is shorter , uses only two variables and only two loops and is almost as efficient (or inefficient) as my earlier program using the second function. It might save a teeny weeny bit on function call overhead though . For example you just split up what I have done in my second loop into two loops , since the loops are not nested you are not losing anything for the extra loop (I think) compared to the program below .
I think your program will be slightly faster than the one below .
#include <stdio.h>
int main(void)
{
int i,j;
for(i=1;i<=10;i++ {
for(j=1;j<=2*i-1;j++) {
if(j<=i) printf("%d",(i+j-1)%10);
else printf("%d",(3*i-j-1)%10);
}
putchar('\n');
}
return 0;
}

Originally posted by Thantos
I deleted my previous post because I was a jerk in it. Sorry. Hey pinko they way you took was much harder then nessary. I did it using 3 variables, and a total of 3 for loops.

Paul to do this pyramids you have to look at the different elements. In this one I found 3 main parts. 1 is the center number, 2 is the outside numbers, and 3 is the number in between.

First the center number. I called this value X. X is increasing by 2 on every line but displaying only the last digit. X increase to a max of 19. A simple loop for that is here: for(x=1;x<20;x+=2).

The second one is the outside numbers. I called this value Z. Z is increasing by 1 on every line. Now I didn't use a for loop on this. I just increased it by 1 on every X loop.

The third is the numbers between Z and X. I called this value Y. Now Y is used two for loops on. One for the values between Z and X, and the second for the values between X and the second Z.

Now that I've explained how to do it you should be able to read the code and understand how to do them in the future.

Code:

int main(void)
{
int x,y,z=0;
for(x=1;x<20;x+=2)
     {
     for(y=z+1;y<x;y++)
          printf("%d",y%10);

     printf("%d",x%10);

     for(y=x-1;y>z;y--)
          printf("%d",y%10);

     printf("\n");
     z++;
     }
}

I said easier not more effient

sorry I misunderstood