2D Polygon Rotation

#include<stdio.h>

#include<conio.h>

#include<math.h>

#include<graphics.h>

struct s

{ int x,y ;

};

void main()

{ int n;

int gd= DETECT ,gm;

 initgraph(&gd,&gm,"c:\\tc\\bgi");

 struct s inp[10],out[10];

 printf("\n Enter the no of vertices");

 scanf("%d",&n);

 for(int i=0;i<n;i++)

   { 

scanf ("%d%d",&inp[i].x&inp[i].y);

   }

   int a;

   printf("\n Enter the rotational angle");

   scanf ("%d",&a);

   a= a* (3.14/180);

   for(i=0;i<n;i++)

    { out[i].x= (inp[i].x * cos(a)) - (inp[i].y*sin(a));

      out[i].y = (inp[i].x * sin(a)) + (inp[i].y* cos(a));

      }

      inp[n]= inp[0];

      out[n] = out[0];

      for(i=0;i<n;i++)

       { setcolor(7);

           line(inp[i].x,inp[i].y,inp[i+1].x,inp[i+1].y);

           }

           getch();

           for(i=0;i<n;i++)

           { printf ("%d%d",out[i].x,out[i].y);

           }

           getch();

           for(i=0;i<n;i++)

           {

           setcolor(5);

           line(out[i].x,out[i].y,out[i+1].x,out[i+1].y);

           }

           getch();

           closegraph();

           }