const _isSameSet = (s1, s2) => {
                // 补全代码
                let arr1=Array.from(s1).sort((a,b)=>a.charCodeAt()-b.charCodeAt())
                let arr2=Array.from(s2).sort((a,b)=>a.charCodeAt()-b.charCodeAt())
                return JSON.stringify(arr1)===JSON.stringify(arr2)
            }