Xiaohong participates in a singing competition. She shakes hands with each of the contestants once, a total of 6 handshakes. How many people participated in the singing competition?
小红参加唱歌比赛，她和参赛的小选手每个人握1次手，一共握了6次，参加唱歌比赛一共有多少人．
<gadget id="calculator">6 + 1</gadget>
<output>7</output>

<result>7</result>