feat(Go-Tool)：

2021/03/02: 新增字符串匹配 暴力匹配、KMP匹配、SunDay匹配算法
            2021/03/02: 修复Rand包随机获取方法

util/rand/RandObjectByWeight.go

@@ -0,0 +1,62 @@
+/*
+ *  @Author : huangzj
+ *  @Time : 2021/2/23 20:50
+ *  @Description：
+ */
+
+package rand
+
+func GetAwardWeightByWeight(awardWeight []*AwardWeight) *AwardWeight {
+	//求总权重
+	weight := 0
+	for _, award := range awardWeight {
+		weight += award.Weight
+	}
+	randNum := GetRandInt(1, weight)
+	sum := 0
+	for _, award := range awardWeight {
+		sum += award.Weight
+		if sum >= randNum {
+			return award
+		}
+	}
+	return nil
+}
+
+//根据权重不放回的抽取，出参是：抽到的道具、剩余没有抽的道具
+func GetByWeightWithLeftAward(awardWeight []*AwardWeight) (*AwardWeight, []*AwardWeight) {
+	weight := 0
+	leftAwards := make([]*AwardWeight, 0)
+	for _, award := range awardWeight {
+		weight += award.Weight
+	}
+	randNum := GetRandInt(1, weight)
+	sum := 0
+	for index, award := range awardWeight {
+		sum += award.Weight
+		if sum >= randNum {
+			//如果获取到奖励则将当前获取的奖励扣除
+			leftAwards = append(awardWeight[0:index], awardWeight[index+1:]...)
+			return award, leftAwards
+		}
+	}
+	return nil, leftAwards
+}
+
+// 根据权重不放回的抽取X个元素，直接返回这些元素
+// 入参：奖池、抽取数量，出参：获得的所有道具，剩余的其他道具
+func GetSomeAwardsFromPool(srcAwardPool []*AwardWeight, count int) ([]*AwardWeight, []*AwardWeight) {
+	if count > len(srcAwardPool) {
+		panic("抽取数量不对")
+	}
+	var finalAwardList []*AwardWeight
+	var award *AwardWeight
+	var leftAward = make([]*AwardWeight, len(srcAwardPool))
+	copy(leftAward, srcAwardPool)
+
+	for i := 0; i < count; i++ {
+		award, leftAward = GetByWeightWithLeftAward(leftAward)
+		finalAwardList = append(finalAwardList, award)
+	}
+	return finalAwardList, leftAward
+}