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1652. Defuse the Bomb
Solved
Easy
Topics
Companies
Hint
You have a bomb to defuse, and your time is running out! Your informer will provide you with a circular array code of length of n and a key k.

To decrypt the code, you must replace every number. All the numbers are replaced simultaneously.

If k > 0, replace the ith number with the sum of the next k numbers.
If k < 0, replace the ith number with the sum of the previous k numbers.
If k == 0, replace the ith number with 0.
As code is circular, the next element of code[n-1] is code[0], and the previous element of code[0] is code[n-1].

Given the circular array code and an integer key k, return the decrypted code to defuse the bomb!

 

Example 1:

Input: code = [5,7,1,4], k = 3
Output: [12,10,16,13]
Explanation: Each number is replaced by the sum of the next 3 numbers. The decrypted code is [7+1+4, 1+4+5, 4+5+7, 5+7+1]. Notice that the numbers wrap around.
Example 2:

Input: code = [1,2,3,4], k = 0
Output: [0,0,0,0]
Explanation: When k is zero, the numbers are replaced by 0. 
Example 3:

Input: code = [2,4,9,3], k = -2
Output: [12,5,6,13]
Explanation: The decrypted code is [3+9, 2+3, 4+2, 9+4]. Notice that the numbers wrap around again. If k is negative, the sum is of the previous numbers.

Author: Gauranshgoel123

defuse-the-bomb.java

@@ -0,0 +1,25 @@
+class Solution {
+    public int[] decrypt(int[] code, int k) {
+        int[] ans=new int[code.length];
+        if(k==0) return ans;
+        int start=1;
+        int end=k;
+        int sum=0;
+        int n=code.length;
+        if(k<0){
+            start=n-Math.abs(k);
+            end=n-1;
+        }
+        for(int i=start;i<=end;i++){
+            sum+=code[i];
+        }
+        for(int i=0;i<n;i++){
+            ans[i]=sum;
+            sum-=code[(start)%n];
+            sum+=code[(end+1)%n];
+            start++;
+            end++;
+        }
+        return ans;
+    }
+}