数组中最高和最低的问题

Question

I have got this code working just as the exercise asked except for the highest and lowest values. I have tried doing the max and min thing but Im either putting it in the wrong place or missing something. The way it is now works apart from that it will if you enter for example 1 , 2 , 3, 11, 20 it says the highest is 3.

It needs to come back as such that it shows what you entered and then sorts it, it shows the sum of the numbers and then the highest and lowest.

Where am I going wrong? Im guessing I should be using max and min but I just cant seem to get it to work using those.

<meta charset="UTF-8">
<title>Laskenta</title>
<script>



var yht=0; //total
var luku=0; //numbers entered
var suurin;// largest number entered
var pienin; // smallest number entered
var i;//counter

var heitto=new Array(5);//heitto= throw

for( var i = 0; i < heitto.length; i++) {
heitto[i]=prompt("anna ", i + 1 + " . heitto") 

document.write ("Index " + i + ": " + "heitto = "  + heitto[i]+"<br>");

if (i == 0) {
suurin = heitto[i];
pienin = heitto[i];
}
else {
  if (heitto[i] > suurin) suurin = heitto[i];
  if (heitto[i] < pienin) pienin = heitto[i];
}
yht+=parseInt(heitto[i]);
} 

document.write ("<br>" + "suurin - pienin heittojen " + heitto.sort(function(a, b){return b-a}) + "<br>");
document.write("<br>" +"Syöttämiesi heittojen summa on " ,yht, "<br>");
document.write("<br />Suurin heitto on "+suurin);
document.write("<br />Pienin heitto  on "+pienin);
</script>

Answer 1

Basically you have two issues:

• Strings instead of numerical values for input, thats why 3 is the biggest value, but only when 3 is a string. Order by strings '1', '11', '2', '20', '3' .

   heitto[i] = +prompt("anna ", i + 1 + " . heitto"); // get the numerical value of input // ^ 

• Results for comparisons does not have the right start value.

   suurin = -Infinity; // initialize with a small number pienin = Infinity; // initialize with a big number 

In the loop for getting the highest and the lowest value, you are compare strings, then you get the result, you have, because of the order of strings. For a numerical comparison, it is better to convert both values in advance to a numerical value with either implicit casting to Number with unary + , or explicit with parseInt , parseFloat or Number .

Your sort function is using an implicit casting to number with - . Taht is the reason why you get a numericl sorted array instead of an array with the sort order like above.

 var yht = 0; //total var luku = 0; //numbers entered var suurin; // largest number entered var pienin; // smallest number entered var i; //counter var heitto = new Array(5);//heitto= throw suurin = -Infinity; // initialize with a small number pienin = Infinity; // initialize with a big number for (var i = 0; i < heitto.length; i++) { heitto[i] = +prompt("anna ", i + 1 + " . heitto"); // get the numerical value of input document.write("Index " + i + ": " + "heitto = " + heitto[i] + "<br>"); if (heitto[i] > suurin) { suurin = heitto[i] }; if (heitto[i] < pienin) { pienin = heitto[i] }; yht += parseInt(heitto[i]); } document.write("<br>" + "suurin - pienin heittojen " + heitto.sort(function (a, b) { return b - a }) + "<br>"); document.write("<br>" + "Syöttämiesi heittojen summa on ", yht, "<br>"); document.write("<br />Suurin heitto on " + suurin); document.write("<br />Pienin heitto on " + pienin);