somebody help me in this recursive pgm???

[ashwini jayaraman]

int rec(int n1)
{
int x=8;

if(n1<=80)
{
int n1=x+rec(n1);
return(n1);
}
else
return 0;
}
#include<stdio.h>
int rec(int n);
void main()
{
int n;
printf("enter no");
scanf("%d",&n);
rec;
printf("%d",rec);
}

I want 8*10= 80 to be printed!!!!

 

[jayanth.devarayanadurga]

Can you expalain what you are trying to do?

---

Code C - [expand]
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int rec(int n1)
{
    int x=8;
 
    if(n1<=80)
    {
        int n2=x+rec(n1);   //if n1 = 80 then n2 = 88
        return(n2);
    }
    else
    return 0;
}
#include<stdio.h>
 
int rec(int n);
 
void main()
{
    int n, m;
    printf("enter no");
    scanf("%d",&n);
    m = rec(n);
    printf("%d", m);
}

---

 

[YEAR_]

if(n1<=80)
{
n1=x+rec(n1);
return(n1);
}

This will put your program in an infinite loop.
The problem with the code is
1. you are using n1 as a case condition.
2. your program is recursively calling itself without modifying n1. n1 can't be updated unless the following line is executed.

n1=x+rec(n1);

what you can do for example is

n1 = n1 * x;
rec(n1);
*but if you write it like
n1 = n1 + x;
you will get 18, as only the first computation(round) result is being returned.