C/math.h/tgamma

    
//Declaration: float tgammaf(float arg); 
               double tgamma(double arg); 
               long double tgammal(long double arg);  
 
  
  #include <math.h>
  #include <stdio.h>
  int main(void)
  {
    printf("%f\n", tgamma (1.2));
    return 0;
  }
         
        /*0.918169*/