Need help with program that prints a triangle of @ symbols

**Kelton2** · 01-01-2015

I'm making a program that prints a triangle of @ signs given rows (but not columns). For example, the output with rows = 4 would be:
@@@@
@@@
@@
@
and rows = 3 would be:
@@@
@@
@
However, trying to make this has given me a program that does something similar (but not the same): for example, with my current program rows = 4 outputs:
@@@@
@@@
@@
@
and rows = 3 gives
@@@
@@
@
It seems that it's just missing a space (and therefore a setw and setfill), but I found 2 problems:
1. The space needs to not apply to the first line.
2. I can't get it to make a space before each row without making a space between each column.
My current code is:

Code:

  #include <iostream>
#include <iomanip>
using namespace std;
int main ( ) {
    int rows;
    cout << "How many rows? ";
    cin >> rows;
    cout << endl;
    for(int r = 0; r < rows; r++) {
          
            for(int c = rows; c > r; c--) {
                    cout << "@";
                    }
                   // cout << setw(r);
                    cout << endl;
                   // cout << setw(r);
                    }
            
}

I have tried putting in << setws and << setfills of various values but it seems to always apply to between each column as well as at the start of each row- what do I do?

**Salem** · 01-01-2015

> what do I do?
Perhaps you should try writing out on paper what the actual steps are to solving the problem.

You know, like

Code:

for each row;
  print zero or more spaces;
  print one or more symbols;

Now can you see where you should be printing some spaces?

> I have tried putting in << setws and << setfills of various values but ...
Whilst random experimentation may be fun, and you may occasionally stumble on the correct answer, it isn't a good long term strategy.

**Kelton2** · 01-01-2015

Ah. So:

Code:

(for loop start)
cout << " ";
cout << "@";
(for loop end)

Of course, the number of times it does this is controlled by the for loop.

**Kelton2** · 01-02-2015

Originally Posted by Kelton2

Ah. So:

Code:

(for loop start)
cout << " ";
cout << "@";
(for loop end)

Of course, the number of times it does this is controlled by the for loop.

Ok, that doesn't work. Any other help?

**Kelton2** · 01-02-2015

Never mind, fixed it.

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