程序无法调了，总是显示说明语法错误，客请各位编程大神指导一下
# include<stdio.h>
# include<math.h>
main (void)
float x,y;
{scanf("%f%f",&x,&y);
if (x<=1)
y=exp()+1;
else if (x>1&&5<=x)
y=-4*x+5;
else if (x>5&&10<=x)
y=2*x-1;
else
y=3*x-11;
printf("%f\n",y);
}
恭请各位编程前辈指导一下，这程序错在...