code: function getPathHash(path) {
              var hash = 0;
              var seed = 131;
  
              path.forEach(function (p) {
                  hash = 0x7FFFFFFF & (hash * seed + getPointHash(p) + (p.onCurve ? 1 : 0));
              });
  
              return hash;
          }
docs: 获取路径哈希
  @param {Array} path 路径数组
  
  @return {number} 哈希值