<?php
//$bonus_total总数 $bonus_count个数 $bonus_type类型
function randBonus($bonus_total = 0,$bonus_count = 3,$bonus_type=1){
$bonus_items = array();//结果
$bonus_balance = $bonus_total;//余额
$bonus_avg = number_format($bonus_total/$bonus_count,2);//平均数
$i = 0;
while($i<$bonus_count){
if($i<$bonus_count-1){
$rand = $bonus_type?(rand(1,$bonus_balance*100-1)/100):$bonus_avg;
$bonus_items[] = $rand;
$bonus_balance -= $rand;
}else{
$bonus_items[] = $bonus_balance;
}
$i++;
}
return $bonus_items;
}

$bonus_items = randBonus(100,3,1);
var_dump($bonus_items);
var_dump(array_sum($bonus_items));

function sendRandBonus($total = 0,$count=3,$type=1){
//$total总数 $count个数 $type类型
if($type==1){
$input = range(0.01,$total,0.01);
if($count>1){
$rand_keys = (array)array_rand($input,$count-1);
$last = 0;
foreach($rand_keys as $i=>$key){
$current = $input[$key]-$last;
$items[] = $current;
$last = $input[$key];
}
}
$items[] = $total-array_sum($items);
}else{
$avg = number_format($total/$count,2);
$i = 0;
while($i<$count){
$items[] = $i<$count-1?$avg:($total-array_sum($items));$i++;
}
}
return $items;
}

$items = sendRandBonus(100,3,1);
var_dump($items);

微信随机红包的计算