Adding solution of latest contest

Author: Garvit244

1000-1100q/1020.py

@@ -0,0 +1,51 @@
+'''
+Given an array A of integers, return true if and only if we can partition the array into three non-empty parts with equal sums.
+
+Formally, we can partition the array if we can find indexes i+1 < j with (A[0] + A[1] + ... + A[i] == A[i+1] + A[i+2] + ... + A[j-1] == A[j] + A[j-1] + ... + A[A.length - 1])
+
+ 
+
+Example 1:
+
+Input: [0,2,1,-6,6,-7,9,1,2,0,1]
+Output: true
+Explanation: 0 + 2 + 1 = -6 + 6 - 7 + 9 + 1 = 2 + 0 + 1
+Example 2:
+
+Input: [0,2,1,-6,6,7,9,-1,2,0,1]
+Output: false
+Example 3:
+
+Input: [3,3,6,5,-2,2,5,1,-9,4]
+Output: true
+Explanation: 3 + 3 = 6 = 5 - 2 + 2 + 5 + 1 - 9 + 4
+ 
+
+Note:
+
+3 <= A.length <= 50000
+-10000 <= A[i] <= 10000
+'''
+
+class Solution(object):
+ def canThreePartsEqualSum(self, A):
+ """
+ :type A: List[int]
+ :rtype: bool
+ """
+ total_sum = 0
+ for val in A:
+ total_sum += val
+ 
+ if(total_sum%3 != 0):
+ return False
+ 
+ curr_sum, groups = 0, 0
+ for val in A:
+ curr_sum += val
+ if curr_sum == total_sum/3:
+ curr_sum = 0
+ groups +=1
+ print groups
+ return groups == 3
+ 

1000-1100q/1021.py

@@ -0,0 +1,33 @@
+'''
+Given an array A of positive integers, A[i] represents the value of the i-th sightseeing spot, and two sightseeing spots i and j have distance j - i between them.
+
+The score of a pair (i < j) of sightseeing spots is (A[i] + A[j] + i - j) : the sum of the values of the sightseeing spots, minus the distance between them.
+
+Return the maximum score of a pair of sightseeing spots.
+
+ 
+
+Example 1:
+
+Input: [8,1,5,2,6]
+Output: 11
+Explanation: i = 0, j = 2, A[i] + A[j] + i - j = 8 + 5 + 0 - 2 = 11
+ 
+
+Note:
+
+2 <= A.length <= 50000
+1 <= A[i] <= 1000
+'''
+class Solution(object):
+ def maxScoreSightseeingPair(self, A):
+ """
+ :type A: List[int]
+ :rtype: int
+ """
+ prev_best, result = 0, 0
+ for index in range(0, len(A)):
+ result = max(result, A[index]-index+prev_best)
+ prev_best = max(prev_best, A[index]+index)
+ return result
+ 

1000-1100q/1022.py

@@ -0,0 +1,37 @@
+'''
+Given a positive integer K, you need find the smallest positive integer N such that N is divisible by K, and N only contains the digit 1.
+
+Return the length of N. If there is no such N, return -1.
+
+ 
+
+Example 1:
+
+Input: 1
+Output: 1
+Explanation: The smallest answer is N = 1, which has length 1.
+Example 2:
+
+Input: 2
+Output: -1
+Explanation: There is no such positive integer N divisible by 2.
+Example 3:
+
+Input: 3
+Output: 3
+Explanation: The smallest answer is N = 111, which has length 3.
+'''
+
+class Solution(object):
+ def smallestRepunitDivByK(self, K):
+ """
+ :type K: int
+ :rtype: int
+ """
+ length, value = 0, 0
+ for no_one in range(100000):
+ value = (10*value + 1)%K
+ length += 1
+ if value == 0:
+ return length
+ return -1

1000-1100q/1023.py

@@ -0,0 +1,39 @@
+'''
+Given a binary string S (a string consisting only of '0' and '1's) and a positive integer N, return true if and only if for every integer X from 1 to N, the binary representation of X is a substring of S.
+
+ 
+
+Example 1:
+
+Input: S = "0110", N = 3
+Output: true
+Example 2:
+
+Input: S = "0110", N = 4
+Output: false
+ 
+
+Note:
+
+1 <= S.length <= 1000
+1 <= N <= 10^9
+'''
+
+class Solution(object):
+ def queryString(self, S, N):
+ """
+ :type S: str
+ :type N: int
+ :rtype: bool
+ """
+ for num in range(1, N+1):
+ binary_str = ''
+ while (num != 0):
+ binary_str += str(num%2)
+ num /= 2
+ reversed_str = binary_str[::-1]
+ 
+ if reversed_str not in S:
+ return False
+ return True
+ 

README.md

@@ -7,6 +7,10 @@ Python solution of problems from [LeetCode](https://leetcode.com/).
 ##### [Problems 1000-1100](./1000-1100q/)
 | # | Title | Solution | Difficulty |
 |---| ----- | -------- | ---------- |
+|1023|[Binary String With Substrings Representing 1 To N](https://leetcode.com/problems/binary-string-with-substrings-representing-1-to-n)|[Python](./1000-1100q/1023.py)|Medium|
+|1022|[Smallest Integer Divisible by K](https://leetcode.com/problems/smallest-integer-divisible-by-k)|[Python](./1000-1100q/1022.py)|Medium|
+|1021|[Best Sightseeing Pair](https://leetcode.com/problems/best-sightseeing-pair)|[Python](./1000-1100q/1021.py)|Medium|
+|1020|[Partition Array Into Three Parts With Equal Sum ](https://leetcode.com/problems/partition-array-into-three-parts-with-equal-sum) | [Python](./1000-1100q/1020.py)|Easy|
 |1014|[Capacity To Ship Packages Within D Days](https://leetcode.com/problems/capacity-to-ship-packages-within-d-days/) | [Python](./1000-1100q/1014.py) | Medium|
 |1013|[Pairs of Songs With Total Durations Divisible by 60](https://leetcode.com/problems/pairs-of-songs-with-total-durations-divisible-by-60/)|[Python](./1000-1100q/1013.py)|Easy|
 |1012|[Complement of Base 10 Integer](https://leetcode.com/problems/complement-of-base-10-integer/) | [Python](./1000-1100q/1012.py)|Easy|