Printing a Pyramid of num's

[js2006]

how can a program be constructed to display a pyramid of numbers using a for loops in c++,
it Ask the user to enter a digit(0-9) and display the pyramid with limit up to that number( as shown in output).and after the output is shown , user presses a key to exit.

OUTPUT :

if 5,entered :

                                    1
                                   2 2
                                  3 3 3
                                 4 4 4 4
                                5 5 5 5 5

Press any key to quit

[js2006]

here is a code , which i made how it can be improved to print number instead of Asteriaks as shown in the above Output ,

int size;

while (cin >> size) {
    for (int row=1; row<=size; row++) {
        for (int col=0; col<row; col++) {
            cout << "*";
        }
        cout << endl;  // end the line.
    }
}

output:
*
**
***
****
*****
******

[redhead]

Exchange

cout << "*";

with

cout << row;

And in the future please wrap [ code] and [/code] tags around your sourcecode, it makes it alot more readable.

[js2006]

thanks redhead,

now i want to improve it by limiting the user to take only digits from 0 - 9

also After the output is shown , there is a repsone taken from user

Press any key to exit

please help me with this.

[redhead]

For a starter, here is a C implementation of it

#include <stdio.h>

int main(void)
{
  size_t count=0, i, j;
  /* ask the user for numbers to print */
  printf("How high should the pyramid go ?: ");
  fflush(stdout);
  fscanf(stdin, "%d", &count);
  for(i=1; i <= count; ++i)
    {
      /* calculate privius spaces */
      for(j=(count/2+i); j <= count*2; ++j)
        printf(" ");
      /* show actual number */
      for(j=0; j < i; ++j)
        printf(" %d", i);
      printf("\n");
    }
  return 0;
}

Notice it will only go upto 9, since the number 10 will span far more than what the single space, in order to align the numbers correct, will be able to correct in the pyramid formation.

Now try an make a similar one in ANSI C++ and for educational purpus, try to make one which would handle numbers larger than 10.

I'm on my way out to play some soccer, so for now this will have todo, but when I return, I will give further advices.

[redhead]

now i want to improve it by limiting the user to take only digits from 0 - 9

while(cin >> size)
{
  if(size < 0 || size > 9)
    {
      cout << "Sorry your given number isn't within acceted limits (0-9)" << endl;
      continue;
    }
...

After the output is shown , there is a repsone taken from user

Press any key to exit

hmm... shouldn't this run untill the user explicit exit, or should it just be a single run ??
To accommodate a request running untill the user explicit exits, you would take percausions like

cout << "Please enter a number between 0 and 9, use -1 to quit: ";
while(cin >> size && size >= 0)
...

To accommodate the user unly beeing asked once, and then exit uppon further user interaction, just eliminate your while clause, and simply read from the user, check for valid number, and then print your pyramid.
Then query the user "press anythign to quit" and simply just let the program terminate uppon next linefeed.

[js2006]

Thanks for your support ,red head

Then query the user "press anythink to quit" and simply just let the program terminate uppon next linefeed.

I want to display the Praymid and then shut my programme , as user presses any key

now how can i query user , is it just simply

cout << "Press any Key to Exit";
..... ????????????????

or any other way around ?? , iam a

C++ newbie , doesn't know much , like learn and conquer it.

so please do me a favour !!

Thanks again ,

[redhead]

Read the system (PAUSE) article.
But the easiest way would be something like:

int main()
{
...
  char ch;
...
  cout << "Press enter to exit";
  cin >> ch; 
  return 0;
}

[js2006]

i have done it finally , for programming , i learn now that , try - try try again !!

[h.yusufzai]

Originally Posted by js2006

here is a code , which i made how it can be improved to print number instead of Asteriaks as shown in the above Output ,

int size;

while (cin >> size) {
    for (int row=1; row<=size; row++) {
        for (int col=0; col<row; col++) {
            cout << "*";
        }
        cout << endl;  // end the line.
    }
}

output:
*
**
***
****
*****
******

sorry could u write the full code of this starting form #include<iostream.h>
i cant get this to work....i am a newbie.