C/math.h/exp

    
//Declaration: float expf(float arg); 
               double exp(double arg); 
               long double expl(long double arg);  
 
    
  
  #include <math.h>
  #include <stdio.h>
  int main(void)
  {
      printf("Value of e to the first: %f.", exp(1.0));
 
  }
         
/*
Value of e to the first: 2.718282.*/