04_01_2.cpp

一个C语言词法分析器,一般本科生课程设计都用得上

/* PROGRAM example401A */;
#include "math.h"                                      /*  1  */
#include "stdio.h"				       /*  2  */				   /*  2  */
float x,y ;                                            /*  3  */
float f(float v,float w ){                             /*  4  */
	return sin(w)/log(v);                          /*  5  */
}                                                      /*  6  */
float p(float u){                                      /*  7  */
	return (f(u*0.3,x+u)+sin(u))/exp(u);           /*  8  */
}                                                      /*  9  */
void main(){                                           /*  10 */
	printf ("please input x: ");                   /*  11 */
	scanf("%f",&x);                                /*  12 */
	y=(p(x)*p(x)+log(5))/(p(x+5)-abs(x))*p(x+2);   /*  13 */
	printf ("y(x)=%f\n",y);                        /*  14 */
}                                                      /*  15 */