#include<stdio.h> #include<conio.h> void main() { int num=1342; clrscr(); printf( "%d" ,printf( "%d" ,printf( "%d" ,num))); getch(); } Output : 134241 How ? Firstly Inner printf is executed which results in printing 1324 This Printf Returns total number of Digits i.e 4 and second inner printf will looks like printf( "%d" ,printf( "%d" ,4)); It prints 4 and Returns the total number of digits i.e 1 (4 is single digit number ) printf( "%d" ,1); It prints simply 1 and output will looks like 132441 Rule : Inner printf returns Length of string printed on screen to the outer printf