Create Range Sum Query - Immutable.py

Author: palashsharma891

Dynamic Programming/Easy/Range Sum Query - Immutable.py

@@ -0,0 +1,34 @@
+class NumArray:
+
+    def __init__(self, nums: List[int]):
+        self.nums = nums
+        self.sum = [0] * (len(self.nums)+1)
+        if len(nums):
+            self.sum[0] = nums[0]
+            for i in range(1, len(nums)):
+                self.sum[i] = self.sum[i-1] + nums[i]
+        
+    def sumRange(self, left: int, right: int) -> int:
+        if left == 0:
+            return self.sum[right]
+        else:
+            return self.sum[right] - self.sum[left-1]
+
+# Your NumArray object will be instantiated and called as such:
+# obj = NumArray(nums)
+# param_1 = obj.sumRange(left,right)
+'''class NumArray:
+
+    def __init__(self, nums: List[int]):
+        self.nums = nums
+        self.sum = 0#] * len(self.nums)
+        
+    def sumRange(self, left: int, right: int) -> int:
+        self.sum = 0
+        for i in range(left, right+1):
+            self.sum += self.nums[i]
+        return self.sum#[right] - self.sum[left-1]
+
+# Your NumArray object will be instantiated and called as such:
+# obj = NumArray(nums)
+# param_1 = obj.sumRange(left,right)'''