Wha'ts wrong

I can't seem to find the problem with this program. I've been looking over it for a long time, and i just can't find the error. It comes up with around 8 errors, but i think only one is causing the rest or the errors.

Code:

#include <stdlib.h>
#include <stdio.h>

struct tree 
{
	char info;
	struct tree *left;
	struct tree *right;
};

struct tree *root;
struct tree *stree(struct tree *root, struct tree *r, char info);
void print_tree(struct tree *root, int 1);

void main(void)
{
	char s[80];
	root = NULL;

	do
	{
		printf("Enter a letter: ");
		gets(s);
		if(!root) root = stree(root, root, *s);
		else stree(root, root, *s);
	}while(*s);
	print_tree(root, NULL);
}

struct tree *stree(struct tree *root, struct tree *r, char info)
	{
		if(!r)
		{
			r = (struct tree *) malloc(sizeof(struct tree));
			if(!r)
			{
				printf("Out of Memory\n");
				exit(0);
			}
			r->left = NULL;
			r->right = NULL;
			r->info = info;
			if(!root) return r;
			if(info<root->info) root->left = r;
			else root->right = r;
			return r;
		}
		if(info<r->info) stree(r, r->left, info);
		else
			stree(r, r->right, info);
	}
void print_tree(struct tree *r, int 1)
	{
		int i;
		if (!r)return;

		print_tree(r->right, 1+1);
		for(i=0; i<1; ++i) printf(" ");
		printf("%c\n", r->info);
		print_tree(r->left, 1+1);
	}

1. What is the program supposed to do?
2. What are the errors that you get?
3. Change "void main()" to "int main()".
4. You most probably do not need a global variable, in this case the one named root.

Well, there are quite a few errors. For example, when you declare a function, you use a variable name which is one character long and begins with a number:

void print_tree(struct tree *root, int 1);

In the same above function, you don't need the "struct" keyword. "tree" already describes the type of root.

So these two mistakes repeat everywhere in the code.

To be fair, the second is not a mistake, as far as I know it is just a C style of doing things... though I believe C programmers tend to use typedef to eliminate the need for that anyway.

this program prints a binary tree depending on the characters you enter.
The errors have to do with a missing '{' , ')', or ';' .
The first error says: '{' : missing function header (old-style formal list?)

ps- this is the whole program, it can be copied and pasted into a compiler. I use Visual Studio 2005.

> void print_tree(struct tree *root, int 1);
This 'l' (ell) looks rather like a 1 (one)
Numbers cannot be identifiers.

Yep, that was it.
Thank you all for the help, it works now.