How to only accept a certain precision (so many decimals places) in scanf?

Question

In scanf() function I want to take only upto decimal values.Can we achieve it? For example for displaying upto two decimal places we use printf(\"%.2f\",

Answer 1

1. include stdlib.h
2. include math.h
3. IF function pow from math.h fails to compile, must compile with gcc file.c -o file -lm
4. TRY example :

Input : 13254.45488

Output: 13254.45

void main()
{

    int x,y,i ;
    int precision = 2 ; /*Insert precision here*/
    char a[precision] ;
    long double z,result ;

    printf( "Input : " );   
    scanf( "%d" , &x );

    for ( i = 0 ; i <= precision  ; i++ )
    {

        a[i] = getchar();

        if ( a[i] == 10 ) break;

    }
    
    a[0] = '0';
    a[i] = '\0';

    y = atoi(a);
    z = y / pow( 10 , i-1 );
    result = x ;

    if ( z != 0 ) result = result + z ;

    printf( "Output: " );   
    printf( "%.*Lf\n", i-1 , result );

}