一段求圆形周长和面积的程序错误原因？

Question

#include
#define PI 3.14
main()
{ float r ,s , l;

printf("please input r:\n");
scanf("%f”,&r);
if (r>=0)

{s=pi*r*r;
l=2*i*r ;
printf("the area is %f\n",s);
printf("the circumference is %f\n",l);}
else

printf("input error!\n");
}

总是提示第8行和第9行错误：

for statement missing ； in function main

检查了半天，每找到原因，求大神指导

Answer 1

 #include <stdio.h>
   #define PI 3.14
int main()
{ float  r ,s , l;  
 printf("please input r:\n");
 scanf("%f",&r); /后括号写成全角了
    if (r>=0)                        
      {s=PI*r*r; // pi大写
      l=2*PI*r ;
      printf("the area is %f\n",s); 
printf("the circumference is %f\n",l);}
else  
printf("input error!\n"); 
 }