C Programming - Input / Output - Discussion

What is the purpose of 2 in "2. 1f"?

It mean there are all 2 decimal values which is going to print and. 1 mean there is one value after decimal.

No it's wrong sharma. 2 means it takes 2 empty spaces before printing a value on the screen.

int main()
{
float a=3.15529;
printf("%3.1f\n", a);
return 0;
}

What is the answer for this?

3.2 is the answer.

3 means it will take 3 decimal values into consideration.

printf("%9.2f",12.45);

This statement outputs four spaces and then 12.45. Those four spaces plus 12.45 (five characters total) equal the 9 in the width.

Only two values are shown to the right of the decimal because .2 is used in the %f conversion character.

#include <stdio.h>
int main()
{
float sample1 = 34.5;
float sample2 = 12.3456789;
printf("%%9.1f = %9.1f\n",sample1);
printf("%%8.1f = %8.1f\n",sample1);
printf("%%7.1f = %7.1f\n",sample1);
printf("%%6.1f = %6.1f\n",sample1);
printf("%%5.1f = %5.1f\n",sample1);
printf("%%4.1f = %4.1f\n",sample1);
printf("%%3.1f = %3.1f\n",sample1);
printf("%%2.1f = %2.1f\n",sample1);
printf("%%1.1f = %1.1f\n",sample1);
printf("%%9.1f = %9.1f\n",sample2);
printf("%%9.2f = %9.2f\n",sample2);
printf("%%9.3f = %9.3f\n",sample2);
printf("%%9.4f = %9.4f\n",sample2);
printf("%%9.5f = %9.5f\n",sample2);
printf("%%9.6f = %9.6f\n",sample2);
printf("%%9.7f = %9.7f\n",sample2);
printf("%%9.6f = %9.6f\n",sample2);
printf("%%9.7f = %9.7f\n",sample2);
printf("%%9.8f = %9.8f\n",sample2);
return(0);
}

Output:

%9.1f = 34.5
%8.1f = 34.5
%7.1f = 34.5
%6.1f = 34.5
%5.1f = 34.5
%4.1f = 34.5
%3.1f = 34.5
%2.1f = 34.5
%1.1f = 34.5
%9.1f = 12.3
%9.2f = 12.35
%9.3f = 12.346
%9.4f = 12.3457
%9.5f = 12.34568
%9.6f = 12.345679
%9.7f = 12.3456793
%9.8f = 12.34567928

What is the solution for this?

#include<stdio.h>
int main()
{
float a=1244.5678;
scanf("%3.2f",&a);
printf("%f",a);
}

Please explain it clearly.

@Chandu.

1244.567749 is the answer.

This is because you have already put a value into "a" and the max size of float is to give 1244.567749 not 1244.5678 as I think.

int main()
{
float a=3.15529;
printf("%2.1f\n", a);
return 0;
}
2 here represents the 2positions to consider so we take 3.155, since it is 5 we round it as 3.2 and print the value is it.

Am I right?

Someone explain it if I'm wrong.

int main()
{
float a=3.15529;
printf("%b.1f\n", a);
return 0;
}

Varying b simply indents the result. What really matters or rather what will affect the output is the digit after the decimal.

say b=3, in that case the output will be printed upto 3 decimal places.