@@ -0,0 +1,37 @@
+#include<vector>
+#include<algorithm>
+#include<iostream>
+using namespace std;
+
+class Solution {
+public:
+int canCompleteCircuit(vector<int>& gas, vector<int>& cost) {
+const int N = gas.size();
+int j = 0;
+for (int i = 0; i < N; )
+{
+int remain = 0; // 记录当前总的油量
+for (j = 0; j < N; j++) // 向前走j个站点后到达站点k
+{
+int k = (i + j) % N; // 环形, 可能 i + j可能比较大
+remain += gas[k] - cost[k];
+if (remain < 0) break;
+}
+if (j == N) return i; // 恰好走了一圈
+i = i + j + 1; // 跳到下一个有可能的i 继续枚举
+}
+return -1;
+}
+};
+
+// Test
+int main()
+{
+Solution sol;
+vector<int> gas = {1, 2, 3, 4, 5};
+vector<int> cost = {3, 4, 5, 1, 2};
+auto res = sol.canCompleteCircuit(gas, cost);
+cout << res << endl;
+
+return 0;
+}