使用最小化堆实现一个整型的优先队列，实现下列功能：

insert x，将优先级值为x的元素入队

find x，找出优先级值大于x的最小的元素，输出其下标。如果有多个元素优先级值相同输出下标最小的那个。

DECREASE i v，将第i个节点的优先级值减少v。(Using a minimum heap to achieve an integer priority queue, the following functions are implemented:　　　　　　Insert x, adding elements of priority x to the team.　　　　　　Find x finds out the smallest element whose priority value is greater than x, and outputs its subscr ipt. If there are multiple elements with the same priority value, the one with the lowest subscr ipt is output.　　　　　　DECREASE I V reduces the priority value of the I node by v.)