[LeetCode] Add January 14.

solved/LeetCode/Challenges/2020/January/14.cc

@@ -0,0 +1,54 @@
+
+#include <bits/stdc++.h>
+
+using namespace std;
+
+#include "../../../template.cc"
+
+using int64 = long long int;
+
+
+class Solution {
+public:
+    int minOperations(vector<int>& nums, int x) {
+      int target = accumulate(nums.begin(), nums.end(), 0) - x;
+      int j = 0;
+      int best = -1;
+      int acc = 0;
+      for (int i = 0; i < nums.size() && j < nums.size(); i++) {
+        while (j < nums.size() && acc < target) {
+          acc += nums[j];
+          j++;
+        }
+        if (acc == target) {
+          best = max(best, j - i);
+        }
+        acc -= nums[i];
+      }
+      if (best == -1) {
+        return best;
+      }
+      return nums.size() - best;
+    }
+};
+
+struct Test {
+  vector<int> nums;
+  int x;
+  int expected;
+};
+
+int main() {
+  vector<Test> test = {
+    { {1,1,4,2,3}, 5, 2},
+    { {5,6,7,8,9}, 4, -1},
+    { {3,2,20,1,1,3}, 10, 5},
+  };
+  for (auto t : test) {
+    Solution sol;
+    int actual = sol.minOperations(t.nums, t.x);
+    debug(t.nums, t.x, t.expected, actual);
+    assert(t.expected == actual);
+  }
+  return 0;
+}