View Compilation Error

0_0_35020683_17186.cpp:1:1: error: 'include' does not name a type
 include<stdio.h>
 ^
0_0_35020683_17186.cpp: In function 'int main()':
0_0_35020683_17186.cpp:54:82: error: 'scanf' was not declared in this scope
     while(scanf("%lf %lf %lf %lf %lf %lf %lf %lf",&x1,&y1,&x2,&y2,&x3,&y3,&x4,&y4)!=EOF)
                                                                                  ^
0_0_35020683_17186.cpp:54:85: error: 'EOF' was not declared in this scope
     while(scanf("%lf %lf %lf %lf %lf %lf %lf %lf",&x1,&y1,&x2,&y2,&x3,&y3,&x4,&y4)!=EOF)
                                                                                     ^
0_0_35020683_17186.cpp:57:28: error: 'printf' was not declared in this scope
             printf("0.00\n");
                            ^
0_0_35020683_17186.cpp:59:48: error: 'checkx' was not declared in this scope
             printf("%.2lf\n",checkx(x1,x2,x3,x4)*checkx(y1,y2,y3,y4));
                                                ^
0_0_35020683_17186.cpp:59:69: error: 'printf' was not declared in this scope
             printf("%.2lf\n",checkx(x1,x2,x3,x4)*checkx(y1,y2,y3,y4));
                                                                     ^