Add 930-BinarySubarraysWithSum.cpp

Author: Rocky-Dewan

Leet_Code/Random Problem/930-BinarySubarraysWithSum.cpp

@@ -0,0 +1,16 @@
+class Solution {
+public:
+    int numSubarraysWithSum(vector<int>& nums, int goal) {
+        std::unordered_map<int, int> f;
+        f[0] = 1;
+        int cs(0), res(0);
+        for(int p = 0; p < nums.size(); p++){
+            cs += nums[p];
+            int diff = cs - goal;
+            if(f.count(diff)){res += f[diff];}
+            ++f[cs];
+        }
+
+        return res;
+    }
+}