add no.134 answer

leetcode/0134.Gas-Station/Gas.go

@@ -0,0 +1,26 @@
+package leetcode
+
+func canCompleteCircuit(gas []int, cost []int) int {
+	totalGas := 0
+	totalCost := 0
+	currGas := 0
+	start := 0
+
+	for i := 0; i < len(gas); i++ {
+		totalGas += gas[i]
+		totalCost += cost[i]
+		currGas += gas[i] - cost[i]
+
+		if currGas < 0 {
+			start = i + 1
+			currGas = 0
+		}
+	}
+
+	if totalGas < totalCost {
+		return -1
+	}
+
+	return start
+
+}