源程序 include <stdio.h> Include <stdio. h>/* 2-4* int main(void) int main( void double x, y; double x, y printf( Enter x: In); printf( Enter x(X>=0): In) scanf(%lf",&x) scanf("%lf,&x) if(x =0) if(x<=15) 1/X y=4*x/3; else else y=0; y=25*x-10.5; printf( f(%.2f)=%.1fIn",x, y); printf("f(%f)=%.2f\n",x, y); return o return 0源程序 #include <stdio.h> int main(void) { double x, y; printf("Enter x:\n"); scanf("%lf", &x); if(x != 0) y = 1/x; else y = 0; printf("f(%.2f) = %.1f\n", x, y); return 0; } #include <stdio.h> /*例2-4 */ int main(void) { double x, y; printf("Enter x (x>=0):\n"); scanf("%lf", &x); if(x <= 15) y = 4 * x / 3; else y = 2.5 * x - 10.5; printf("f(%f) = %.2f\n", x, y); return 0; }