Insert Operator (Recursion)
Problem Statement
You are given a sequence of numbers of size N. You have to find if there is a way to insert + or - operator in between the numbers so that the result equals K.
import java.io.*; // for handling input/output
import java.util.*; // contains Collections framework
// don't change the name of this class
// you can add inner classes if needed
class Main {
public static int rec(long []arr,long sum,int i){
System.out.println("sum = "+sum);
if(i==arr.length){
if(sum==0){
return 0;
}else{
return 1;
}
}
return rec(arr,sum-arr[i],i+1)*rec(arr,sum+arr[i],i+1);
}
public static void main (String[] args) {
// Your code here
Scanner sc = new Scanner(System.in);
int n = sc.nextInt();
long target = sc.nextLong();
long []arr = new long[n];
for(int i=0;i<n;i++){
arr[i] = sc.nextLong();
}
int sum=(rec(arr,target,0));
System.out.println("sum = "+sum);
if(sum==0){
System.out.println("YES");
}else
{
System.out.println("NO");
}
}
}
