PREVIOUS NEXT CHAPTER

printf C

How to to show output on monitor in C

printf is function in c programming that writes to the standard output.I will explain the working of printf using following program.

#include<stdio.h>

main()

{

int a=2,b=3,c;

char d='e';

float g=2.2;

printf("I will print the value of 'a' on monitor\n");

printf("%d\n",a);

printf("I will print the value of a and b simultaneously");

printf("%d%d\n",a,b);

c=a+b;

printf("I will print sum of a and b");

printf("%d + %d=%d\n",a,b,c);

printf("sum of %d and %d is %d/n",a,b,c");

printf("%c/n",d);

printf("%d%c%f/n",a,d,g");

}

Output of the above program will be

I will print the value of 'a' on monitor

I will print the value of a and b simultaneously

I will print sum of a and b

2+3=5

sum of 2 and 3 is 5

2e2.2

Now I will explain the program

line int a=2,b=3,c declares three variables a,b,c.Value of a will be 2 and value of b will be 3.c is variable to store sum of a and b.

line char d='e' assign character e to d.

line float g=2.2 assign 2.2 to g.

line printf("I will print the value of 'a' on monitor") will print exactly same thing which is inside quotes i.e I will print the value of 'a' on monitor

line printf("%d\n",a) will substitute %d with value of a and it will hence output will be 2

line printf("I will print the value of a and b simultaneously") will print exactly same thing which is inside quotes i.e I will print the value of a and b simultaneously

line printf("%d%d\n",a,b) will substitute first %d with a i.e 2 and second %d with b i.e 3 hence output will be 23

printf("I will print sum of a and b") will print exactly same thing which is inside quotes i.e I will print sum of a and b

line c=a+b will do the sum of a and b i.e 2 and 3 and assign to the c.Hence 5 will be assigned to c;

line printf("%d + %d=%d\n",a,b,c) will substitute first %d with a i.e 2, second %d with b i.e 3,third %d with c i.e 5.symbol + and = will be printed as it is.Hence output will be 2+3=5

line printf("sum of %d and %d is %d/n",a,b,c") will substitute first %d with a i.e 2, second %d with b i.e 3,third %d with c i.e 5. Hence output will be sum of 2 and 3 is 5

line printf("%c/n",d) will print value of d i.e e.Here %c means we are printing character

line printf("%d%c%f/n",a,d,g") will print 2e2.2.%f means It will print float value

What are format specifiers ?

%d,%c,%f which I have used above in program are called format specifiers

We use these to print the desired type of output.If we want to print character we will use %c If we want to print float then %f is used ,If we want to print decimal value %d is used.

char c='a';

printf("%c%d",c,c);

Output will be a97.We used %c to print character value of c variable i.e a.We used %d to print decimal value of c.ASCII value of a is 97 hence decimal value will also be 97.97 will be printed.

PREVIOUS NEXT CHAPTER