Thread: substrings

I just made a program which searches for subtrings from a char* the hard way.
does someone have an algoritm which is better than this?
here's my code...

Code:

#include<iostream.h>
#include<conio.h>
#include<string.h>
#include<stdio.h>
enum Bool{false, true};

Bool search(char sub[], char sup[]){
int subl=strlen(sub), supl=strlen(sup), st=0;
Bool flag = false;
if(supl<subl)return false;                  // sub larger than superstring.
else{
	for(int i=0; i<subl; i++)
	for(int j=st; j<supl && i<subl; j++)
		if(sub[i]==sup[j]){
		flag = true;
		i++;
		}else{
		flag = false;
		i=-1;
		st++;
		break;
		}
	return flag;
}
}

void main(){
clrscr();
char a[20], b[20];
do{
gets(a);
gets(b);

if( search(a, b) )cout<<"Substring !";
else cout<<"Not substring !";
cout<<"\n'q' to quit...\n\n\n";
}while( getch()!='q' );
getch();
}

This code is like noodles;
Even I can't make out the head or tail of it now.
P.S. I dont want to use any standard 'String' class or anything.