FaultDetection

/*
 * By--Umesh Poswal(13CS01010)
 * DEC Assignment
 * 
 * In this program I have made use of 5 gates namely And, Or, Not, Nand, Nor and these are represented by
 *  numbers(i.e each gate type has a number associated with it) 1,2,3,4,5 respectively
 *   
 * and if there are n gates in total then gates are numbered from 0 to n-1
 * 
 * PLease note the input format of the program:-
 *    1.Input two integers --number of inputs and number of gates
 *    2.In build circuit method :-
 *         input is of the format (i1,i2,i3,i4,i5,i6)
 *         where i1=gate type, i2 is gate number   //user don't have to give i2
 *         i3 is gate number whose output is given as input 1
 *         i4 is gate number whose output is given as input 2
 *         i5 and i6 are first and second inputs respectively from the input line
 *         
 *         
 *         So if you are not using the inputs from the input lines or from gate output then give corresponding argument as '-1'
 *         
 *         N.B :- Give same input two times if you are using a Not gate 
 *         
 *         
 *         
 *         Input format to give a fault--user have to give three integers..
 *               first integer=gate number
 *               second integer=input line of gate  i.e input1 or input2 of gate
 *         		 third integer=stuck value i.e 0 or 1
 */
import java.util.*;
class Gates{
	
int Gtype,in1,in2,op;	
}
	
public class circuit {

public static void main(String args[]){
	print("Please read the comments in code to know the exact input format\n\n\n");
	Scanner in=new Scanner(System.in);
	int i,g;
	String str;
	int []arr=new int[130];
	boolean flag=false;
	
	print("Enter number of input lines and number of gates\n");
	
	i=in.nextInt();
	g=in.nextInt();
	
	int []ans=new int[i];
	int fault[]=new int[3];
	print("Enter fault(please see input format in code)\n");
	for(int k=0;k<3;k++)
		fault[k]=in.nextInt();
		
	int list[]=new int[i];
	Gates[] gate=new Gates[g];
		
	print("Enter gate types..\n");
	for(int j=0;j<g;j++){
		gate[j]=new Gates();
	    gate[j].Gtype=in.nextInt();
	    if(gate[j].Gtype<0 || gate[j].Gtype>5){
	    	print("\nWrong Input !!  Gate types are from 1 to 5\n By default this gate has been made of type 1 i.e And gate\n");
	    	gate[j].Gtype=1;
	    }
	}
	print("Now build the Circuit...give gate type==-5 when finished");
	int cou=0;
	arr[cou]=in.nextInt();
	while(arr[cou]!=-5){
		cou++;
		arr[cou]=in.nextInt();
	}
		
	
	int i1,i3,i4,i5,i6;

	for(int t=0;t<Math.pow(2, i);t++){
		str=Integer.toBinaryString(t);
		for(int jj=0;jj<str.length();jj++)
			list[i-str.length()+jj]=str.charAt(jj)-'0';
					
		cou=0;
		int num=0;
		i1=arr[cou];cou++;
		while(i1!=-5){
			
			i3=arr[cou];cou++;
			i4=arr[cou];cou++;
			i5=arr[cou];cou++;
			i6=arr[cou];cou++;
			Activate(i1,num,i3,i4,i5,i6,list,gate);
			i1=arr[cou];cou++;
			num++;
		}
		int out1,out2;
		out1=gate[g-1].op;
		
		cou=0;num=0;
		i1=arr[cou];cou++;
		while(i1!=-5){
			
			i3=arr[cou];cou++;
			i4=arr[cou];cou++;
			i5=arr[cou];cou++;
			i6=arr[cou];cou++;
			Justify(i1,num,i3,i4,i5,i6,list,gate,fault);
			i1=arr[cou];cou++;
			num++;
		}
		
		out2=gate[g-1].op;
		if(out1!=out2){
			//print("\n");
			flag=true;
			for(int k=0;k<i;k++)
            // print(list[k]+" ");
				ans[k]=list[k];
			break;
		}
	}
	if(flag==true){
		print("\nFault can be detected using test case:\n");
		for(int k=0;k<i;k++)
			print(""+ans[k]);
	}
	else print("\nGiven fault can't be detected !!!");
	in.close();
}
public static void print(String str){
	System.out.print(str);
}
public static void Activate(int i1,int i2,int i3,int i4,int i5,int i6,int[] list,Gates[] gate){
	int ip1,ip2;
	
	if(i3==-1){
		gate[i2].in1=list[i5];
		ip1=list[i5];
	}
	else {
		gate[i2].in1=gate[i3].op;
		ip1=gate[i3].op;
	}
	if(i4==-1){
		gate[i2].in2=list[i6];
		ip2=list[i6];
	}
	else {
		gate[i2].in2=gate[i4].op;
		ip2=gate[i4].op;
	}
	
	switch(i1){
	case 1:
		if(ip1==1)
			gate[i2].op=ip2;
		else 
			gate[i2].op=0;
		break;
	
	case 2:
		if(ip1==0)
			gate[i2].op=ip2;
		else gate[i2].op=1;
		break;
		
	case 3:
		if(ip1==0)
			gate[i2].op=1;
		else if(ip1==1) gate[i2].op=0;
		 break;
	case 4:
		if(ip1==1 && ip2==1)
			gate[i2].op=0;
		else gate[i2].op=1;
		break;
		
	case 5:
		if(ip1==0 && ip2==0)
			gate[i2].op=1;
		else gate[i2].op=0;
		break;
	}
}
public static void Justify(int i1,int i2,int i3,int i4,int i5,int i6,int[] list,Gates[] gate,int [] fault){
	int ip1,ip2;
	
	if(i3==-1){
		gate[i2].in1=list[i5];
		ip1=list[i5];
	}
	else {
		gate[i2].in1=gate[i3].op;
		ip1=gate[i3].op;
	}
	if(i4==-1){
		gate[i2].in2=list[i6];
		ip2=list[i6];
	}
	else {
		gate[i2].in2=gate[i4].op;
		ip2=gate[i4].op;
	}
	
	
	if(i2==fault[0])
	{
		if(i1==3)ip1=fault[2];
		else {if(fault[1]==1)
			
		ip1=fault[2];
		else ip2=fault[2];
	}
	}
	switch(i1){
	case 1:
		if(ip1==1)
			gate[i2].op=ip2;
		else 
			gate[i2].op=0;
		break;
	
	case 2:
		if(ip1==0)
			gate[i2].op=ip2;
		else gate[i2].op=1;
		break;
		
	case 3:
		if(ip1==0)
			gate[i2].op=1;
		else if(ip1==1)gate[i2].op=0;
		  break;
	case 4:
		if(ip1==1 && ip2==1)
			gate[i2].op=0;
		else gate[i2].op=1;
		break;
		
	case 5:
		if(ip1==0 && ip2==0)
			gate[i2].op=1;
		else gate[i2].op=0;
		break;
	}
}
}