#include<math.h>#include<stdio.h>#ifndef M_PI#define M_PI 3.14159265358979323846#endifintmain(intargc,char**argv){longdoublezero=0.0;doublesi=sin(M_PI/2.0);inta=3;floatb=1.5;floatmul=a*b;printf("0 is %Lf, sin(pi/2) is %f and 3*1.5 is %f.\n",zero,si,mul);return0;}