c - Why does ceil return 0.000 in the following code? -

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• what happens float variable when %d used in printf? 2 answers

#include<stdio.h> #include<math.h> int main() { float = 2.5; printf("%d, %f", floor(i), ceil(i)); return 0; } 

although have used %f specifier in printf() ceil, prints 0.000000. why so?

the return type of floor floating point number (double in case). passing "%d" yields undefined behaviour.

you need use %f format specifier. example,

#include <stdio.h> #include<math.h> int main() {   float = 2.5;   printf("%f, %f", floor(i), ceil(i));   return 0; } 

output

2.000000, 3.000000