Error(s):

source_file.c:4:1: warning: return type defaults to ‘int’ [-Wimplicit-int]
 Main()
 ^
source_file.c: In function ‘Main’:
source_file.c:6:1: warning: implicit declaration of function ‘Int’ [-Wimplicit-function-declaration]
 Int(n)
 ^
source_file.c:6:5: error: ‘n’ undeclared (first use in this function)
 Int(n)
     ^
source_file.c:6:5: note: each undeclared identifier is reported only once for each function it appears in
source_file.c:7:1: error: expected ‘;’ before ‘Printf’
 Printf("enter a integer");
 ^
source_file.c:8:1: warning: implicit declaration of function ‘Scanf’ [-Wimplicit-function-declaration]
 Scanf("%d",&n);
 ^
source_file.c:9:1: warning: implicit declaration of function ‘Switch’ [-Wimplicit-function-declaration]
 Switch (n);
 ^
source_file.c:11:1: error: ‘Case’ undeclared (first use in this function)
 Case 1:printf("sunday");break;
 ^
source_file.c:11:6: error: expected ‘;’ before numeric constant
 Case 1:printf("sunday");break;
      ^
source_file.c:11:25: error: break statement not within loop or switch
 Case 1:printf("sunday");break;
                         ^
source_file.c:12:6: error: expected ‘;’ before numeric constant
 Case 2:print("monday");break;
      ^
source_file.c:12:24: error: break statement not within loop or switch
 Case 2:print("monday");break;
                        ^
source_file.c:13:1: warning: label ‘Default’ defined but not used [-Wunused-label]
 Default :printf("invalid input");
 ^
source_file.c:15:1: warning: control reaches end of non-void function [-Wreturn-type]
 }
 ^