Is there a problem with this code because i cant compile it

Code:
#include <stdio.h>
#include <conio.h>
#include <stdlib.h>

float get_value(void);
int main(int argc, char* argv[])

{
      system("cls");
      

}
float get_value(void)
{   
      float x,c;
      char t;
      scanf("\n&#37;c",t);
      if(t=="A"||t=="a")
      {      printf("hi");
              return(t);
      }
      
      else

      { printf("\a\nWrong input");
      }
    
      getch();
}