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You are the encoded form of a data string as follows: consecutive
occurrences of a letter (up to 9) are represented by the letter
followed by the number of occurrences.

For example, the string

a9a3b2c4de

stands for the string

aaaaaaaaaaaabbccccdc

- that is, 12 consecutive occurrences of a, followed by 2 bs, and then
4 cs, followed by a d and finally c

Given an encoded form, you have to output the data string.

Its not entering the two if conditions


[edit]Tidy up, code block added, indentation sorted, spurious blank lines removed - OriginalGriff[/edit]

What I have tried:

#include<stdio.h>
int main()
    {
    int i,n,s;
    char a[100];
    scanf("%d",&s);
    for(i=0;i<s;i++)
        {
        scanf("%c",&a[i]);
        }
    for(i=0;i<s;i++)
        { 
        if((a[i]>='a' && a[i]<='z')&&(a[i+1]>='a'&& a[i+1]<='z'))
            {
            printf("%c",a[i]);
            }
        else if((a[i]>='a' && a[i]<='z') &&(a[i+1]>='2' && a[i+1]<='9'))
            {
            n=a[i+1];
            while(n>0)
                {
                printf("%c",a[i]);
                n=n-1;
                }
            }
        }
    if(a[s-1]>='a'&& a[s-1]<='z')
        {
        printf("%c",a[s-1]);
        }
    return 0;
    }
Posted
Updated 7-Jul-19 21:09pm
v2
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Solution 1

I've indented you code for you, so it's easier to read.
But ... Compiling does not mean your code is right! :laugh:
Think of the development process as writing an email: compiling successfully means that you wrote the email in the right language - English, rather than German for example - not that the email contained the message you wanted to send.

So now you enter the second stage of development (in reality it's the fourth or fifth, but you'll come to the earlier stages later): Testing and Debugging.

Start by looking at what it does do, and how that differs from what you wanted. This is important, because it give you information as to why it's doing it. For example, if a program is intended to let the user enter a number and it doubles it and prints the answer, then if the input / output was like this:
Input   Expected output    Actual output
  1            2                 1
  2            4                 4
  3            6                 9
  4            8                16
Then it's fairly obvious that the problem is with the bit which doubles it - it's not adding itself to itself, or multiplying it by 2, it's multiplying it by itself and returning the square of the input.
So with that, you can look at the code and it's obvious that it's somewhere here:
int Double(int value)
   {
   return value * value;
   }

Once you have an idea what might be going wrong, start using teh debugger to find out why. Put a breakpoint on your line:
myaverage.DisplayAverage();

and run your app. Think about what each line in the code should do before you execute it, and compare that to what it actually did when you use the "Step over" button to execute each line in turn. Did it do what you expect? If so, move on to the next line.
If not, why not? How does it differ?

This is a skill, and it's one which is well worth developing as it helps you in the real world as well as in development. And like all skills, it only improves by use!

Yes, I could probably tell you what "the problem" is - but it's not difficult to do this yourself, and you will learn something really worthwhile at the same time!

Start by following exactly what happens when your loops begin: what are the values of the variables. (Trust me, that's a pretty big hint!)
   
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Solution 2

Thre are (at least :-) ) two problems with you code.
  1. Dangling newline character in scanf (see, for instance How do I avoid a "dangling" newline when reading single character user input[^])
  2. Wrong interpretation of the read digit: if you read '4' then you have to repeat ('4'-'0') times


Try
#include <stdio.h>
int main()
{
  int i,n,s;
  char a[100];

  scanf("%d",&s);
  for(i=0;i<s;i++)
  {
    scanf(" %c",&a[i]);
  }

  for(i=0;i<s;i++)
  {
    if((a[i]>='a' && a[i]<='z')&&(a[i+1]>='a'&& a[i+1]<='z'))
    {
      printf("%c",a[i]);
    }
    else if((a[i]>='a' && a[i]<='z') &&(a[i+1]>='2' && a[i+1]<='9'))
    {
      n=a[i+1]-'0';
      while(n>0)
      {
        printf("%c",a[i]);
        n=n-1;
      }
    }
  }

  if(a[s-1]>='a'&& a[s-1]<='z')
  {
    printf("%c",a[s-1]);
  }
  printf("\n");
  return 0;
}
   
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Solution 3

Advice learn to indent properly your code, it helps reading. See your question.
Programmer's editors have this kind of features.
Notepad++ Home[^]
ultraedit[^]

Your exercise is about Run-length encoding - Wikipedia[^].

Since you are working with positions i and i+1, you need to stop the loop 1 step earlier.

Quote:
Its not entering the two if conditions

When you don't understand why your code don't do what you expect, the answer is debugger

There is a tool that allow you to see what your code is doing, its name is debugger. It is also a great learning tool because it show you reality and you can see which expectation match reality.
When you don't understand what your code is doing or why it does what it does, the answer is debugger.
Use the debugger to see what your code is doing. Just set a breakpoint and see your code performing, the debugger allow you to execute lines 1 by 1 and to inspect variables as it execute.

Debugger - Wikipedia, the free encyclopedia[^]

Mastering Debugging in Visual Studio 2010 - A Beginner's Guide[^]
Basic Debugging with Visual Studio 2010 - YouTube[^]
The debugger is here to show you what your code is doing and your task is to compare with what it should do.
There is no magic in the debugger, it don't find bugs, it just help you to. When the code don't do what is expected, you are close to a bug.
   
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Solution 4

#include<stdio.h>
#include<string.h>
int main()
{
int num;
char b;
while(scanf("%c %d",&b,&num)==2)
{
while(num--)
{
printf("%c",b);
}
}
return 0;
}
   
Comments
CHill60 8-Jul-19 4:38am
   
The homework from the question is long overdue, and doing someone else's homework does not help anyone

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