suppose there is an array like this
var qq = [
  
  {
    "group": 100,
    "info": {"event": 123},
    "main": true,
  },
  {
    "group": 100,
    "info": {"event": 323},
    "main": true,
    "sp": 1
  },
  {
    "group": 103,
    "info": {"event": 123},
    "main": true,
    "sp": 13,
  },
  {
    "group": 103,
    "info": {"event": 323},
    "main": true,
    "sp": 10
  },
  {
    "group": 103,
    "info": {"event": 123},
    "main": true,
    "sp": 1
  }
  ];
 group is in the same group as the number. 
 I want to put sp 1 in the first group in the same group, and change main to false. 
 how to achieve this? Is there a big god who can try it for me? 
the end result should be like this
var qq = [
   {
    "group": 100,
    "info": {"event": 323},
    "main": false,
    "sp": 1
  },
  {
    "group": 100,
    "info": {"event": 123},
    "main": true,
  },
  {
    "group": 103,
    "info": {"event": 123},
    "main": false,
    "sp": 1
  },
  {
    "group": 103,
    "info": {"event": 123},
    "main": true,
    "sp": 13,
  },
  {
    "group": 103,
    "info": {"event": 323},
    "main": true,
    "sp": 10
  }
  ];