<?php
function random(){
    $neg = 0;
    $pos = 0;
    $vet = array();
 
    echo "Números sorteados: ";
    for ($i=1; $i<=20; $i++) {
        $temp = rand(-100, 100);
        $vet[$i] = $temp;
 
        if ($temp <= 0) {
            $neg++;
        } else {
            $pos+=$temp;
        }
 
 
        // Obs.: você poderia exibir tudo sem utilizar um array apenas com a variavel $temp, mas como o exercício pediu, deixei a solução abaixo com o array:    
        if($i==20){
            echo $vet[$i] . "\n";
        }else{
            echo $vet[$i] . ",";
        }
 
    }
 
    echo "Soma dos Positivos: " . $pos . "</br> Quantidade de negativos: " . $neg . "</br>";      
} 
 
random();
?>

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