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如何通过js实现随机的四则运算题目效果？

来源：www.45fan.com  2016-11-18 20:13:59

如何通过js实现随机的四则运算题目效果？

本文主要介绍了随机的四则运算题目，这样就可以自动的生成随机的30个四则运算题目了。可以生成随机的四则运算题目给给小学生用，但是还是有问题，小学生啊！他们不知道负数，不知道小数。所以还要加入判定条件。具体代码如下：

switch(Arr[n]){
  case "+":{
  sum=a+b;
  break;
  }
  case "-":{
  sum=a-b;
  while(sum<0){
   var a = GetRandomNum(1,30);
   var b = GetRandomNum(1,30);
   sum=a-b;
  }
  break;
  }
  case "*":{
  sum=a*b;
  break;
  }
  case "/":{
  sum=a/b;
  while(hasDot(sum)){
   var a = GetRandomNum(1,100);
   var b = GetRandomNum(1,100);
   sum=a/b;
   }
  break;
  }

这样负数和小数都没有了。

不过，小学生貌似会分数的运算。于是我又开始试试写分数的。

<body> 
<button class="btn btn-success btn-sm" type='button' onclick="pl_f()">开始生成题目</button>
 <span id="text_f"></span>
 <script>
 function GetRandomNum(Min,Max)
 { 
 var Range = Max - Min; 
 var Rand = Math.random(); 
 return(Min + Math.round(Rand * Range)); 
 }
 function max_num(x,y) {
 var t;
 while (y) {
  t = x%y;
  x = y;
  y = t;
 }
 return x;
 }
 function fenshu(a,b,p) {
 if (p==1) {
  if (a>b) {
  return a+"/"+b;
  }else if(a<b){
  return a+"/"+b;
  }else {
  return 1;
  }
 }else {
  var x=a/p;
  var y=b/p;
  if(y==1){
  return x;
  }else{
  return x+"/"+y;
  }
 }
 } 
 function pl_f() {
 var son_a = GetRandomNum(1,30); 
 var par_b = GetRandomNum(1,30);
 var son_c = GetRandomNum(1,30); 
 var par_d = GetRandomNum(1,30); 
 var X=son_a+"/"+par_b;
 var Y=son_c+"/"+par_d;
 document.write("第一个分数："+X+"<br>");
 document.write("第二个分数"+Y+"<br>");
 max_x=max_num(son_a,par_b);
 max_y=max_num(son_c,par_d);
 document.write("第一个最大公约数"+max_x+"<br>");
 document.write("第二个最大公约数"+max_y+"<br>");
 var N=fenshu(son_a,par_b,max_x);
 var M=fenshu(son_c,par_d,max_y);
 document.write("第一个分数化简："+N+"<br>");
 document.write("第二个分数化简"+M);
 }
 </script>
 </body>

这个可以动态的生成两个分数，然后输出这个分数分子和分母的最大公约数。最后输出分子的最简式。

最后就是将分数放入整数一起了!

<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml">
 <head>
 <title> new document </title>
 <meta http-equiv="Content-Type" content="text/html; charset=utf-8">
 <meta name="generator" content="editplus" />
 <meta name="author" content="" />
 <meta name="keywords" content="" />
 <meta name="description" content="" />
 </head>

 <body>
 <button type='button' onclick="play_all()">开始生成题目</button>
 <span id="text"></span>
 </body>
 <script>
 function GetRandomNum(Min,Max)
 { 
 var Range = Max - Min; 
 var Rand = Math.random(); 
 return(Min + Math.round(Rand * Range)); 
 }
 function max_num(x,y) {
 var t;
 while (y) {
  t = x%y;
  x = y;
  y = t;
 }
 return x;
 }
 function fenshu(a,b,p) {
 if (p==1) {
  if (a>b) {
  return a+"/"+b;
  }else if(a<b){
  return a+"/"+b;
  }else {
  return 1;
  }
 }else {
  var x=a/p;
  var y=b/p;
  if(y==1){
  return x;
  }else{
  return x+"/"+y;
  }
 }
 }
 function f_count(a,b,c,d) {
  var Arr = ["+","-","*","/"]; 
  var n = GetRandomNum(0,3);
  switch(Arr[n]){
  case "+":{
  var sum_x=(a*d)+(b*c);
  var sum_y=b*d;
  max_x=max_num(sum_x,sum_y);
  max_y=max_num(sum_x,sum_y);
  var N=fenshu(sum_x,sum_y,max_x);
  return a+"/"+b+"+"+c+"/"+d+"="+N;
  break;
  }
  case "-":{
  var sum_x=(a*d)-(b*c);
   while (sum_x<0) {
   var a = GetRandomNum(1,30); 
   var b = GetRandomNum(1,30);
   var c = GetRandomNum(1,30); 
   var d = GetRandomNum(1,30);
   var sum_x=(a*d)-(b*c);
   }
  var sum_y=b*d;
  max_x=max_num(sum_x,sum_y);
  max_y=max_num(sum_x,sum_y);
  var N=fenshu(sum_x,sum_y,max_x);
  return a+"/"+b+"-"+c+"/"+d+"="+N;
  break;
  }
  case "*":{
  var sum_x=a*c;
  var sum_y=b*d;
  max_x=max_num(sum_x,sum_y);
  max_y=max_num(sum_x,sum_y);
  var N=fenshu(sum_x,sum_y,max_x);
  return a+"/"+b+"*"+c+"/"+d+"="+N;
  break;
  }
  case "/":{
  var sum_x=a*d;
  var sum_y=b*c;
  max_x=max_num(sum_x,sum_y);
  max_y=max_num(sum_x,sum_y);
  var N=fenshu(sum_x,sum_y,max_x);
  return a+"/"+b+"÷"+c+"/"+d+"="+N;
  break;
  }
  }
 }
 function count(a,b){
  var Arr = ["+","-","*","/"]; 
  var n = GetRandomNum(0,3);
  switch(Arr[n]){
  case "+":{
  var sum=a+b;
  return a+"+"+b+"="+sum;
  break;
  }
  case "-":{
  var sum=a-b;
  while(sum<0){
   var a = GetRandomNum(1,30);
   var b = GetRandomNum(1,30);
   var sum=a-b;
  }
  return a+"-"+b+"="+sum;
  break;
  }
  case "*":{
  var sum=a*b;
  return a+"*"+b+"="+sum;
  break;
  }
  case "/":{
  var sum=a/b;
  while(a%b!==0){
   var max_x=max_num(a,b);
   var N=fenshu(a,b,max_x);
   return a+"÷"+b+"="+N;
  }
  return a+"÷"+b+"="+sum;
  break;
  }
  }
 }
 function pl_f() {
 var son_a = GetRandomNum(1,30); 
 var par_b = GetRandomNum(1,30);
 var son_c = GetRandomNum(1,30); 
 var par_d = GetRandomNum(1,30);
 var suma=f_count(son_a,par_b,son_c,par_d);
 return suma;
 }
 function pl() {
  var a = GetRandomNum(1,30); 
  var b = GetRandomNum(1,30);
  var sumb=count(a,b);
  return sumb;
 }
 function play_all() {
  for (i = 1; i <=30; i++) {
  var a = GetRandomNum(0,1);
  document.getElementById("text").innerHTML+=("<br>"+"第"+i+"题：");
  switch (a) {
   case 0:
   var A=pl();
   document.getElementById("text").innerHTML+=(A);
   break;
   case 1:
   var B=pl_f();
   document.getElementById("text").innerHTML+=(B);
   break;
  }
  }
 }
 </script>
</html>

执行完节目就成这样的啦

如何通过js实现随机的四则运算题目效果？

最后上个答案和题目分开的版本！

<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml">
 <head>
 <title> new document </title>
 <meta http-equiv="Content-Type" content="text/html; charset=utf-8">
 <meta name="generator" content="editplus" />
 <meta name="author" content="" />
 <meta name="keywords" content="" />
 <meta name="description" content="" />
 </head>

 <body>
 <button type='button' onclick="play_all()">开始生成题目</button>
 <span id="text"></span>
 <span id="text2"></span>
 </body>
 <script>
 function GetRandomNum(Min,Max)
 { 
 var Range = Max - Min; 
 var Rand = Math.random(); 
 return(Min + Math.round(Rand * Range)); 
 }
 function max_num(x,y) {
 var t;
 while (y) {
  t = x%y;
  x = y;
  y = t;
 }
 return x;
 }
 function fenshu(a,b,p) {
 if (p==1) {
  if (a>b) {
  return a+"/"+b;
  }else if(a<b){
  return a+"/"+b;
  }else {
  return 1;
  }
 }else {
  var x=a/p;
  var y=b/p;
  if(y==1){
  return x;
  }else{
  return x+"/"+y;
  }
 }
 }
 function f_count(a,b,c,d) {
  var Arr = ["+","-","*","/"]; 
  var n = GetRandomNum(0,3);
  switch(Arr[n]){
  case "+":{
  var sum_x=(a*d)+(b*c);
  var sum_y=b*d;
  max_x=max_num(sum_x,sum_y);
  max_y=max_num(sum_x,sum_y);
  var N=fenshu(sum_x,sum_y,max_x);
  return a+"/"+b+"+"+c+"/"+d+"="+N;
  break;
  }
  case "-":{
  var sum_x=(a*d)-(b*c);
   while (sum_x<0) {
   var a = GetRandomNum(1,30); 
   var b = GetRandomNum(1,30);
   var c = GetRandomNum(1,30); 
   var d = GetRandomNum(1,30);
   var sum_x=(a*d)-(b*c);
   }
  var sum_y=b*d;
  max_x=max_num(sum_x,sum_y);
  max_y=max_num(sum_x,sum_y);
  var N=fenshu(sum_x,sum_y,max_x);
  return a+"/"+b+"-"+c+"/"+d+"="+N;
  break;
  }
  case "*":{
  var sum_x=a*c;
  var sum_y=b*d;
  max_x=max_num(sum_x,sum_y);
  max_y=max_num(sum_x,sum_y);
  var N=fenshu(sum_x,sum_y,max_x);
  return a+"/"+b+"*"+c+"/"+d+"="+N;
  break;
  }
  case "/":{
  var sum_x=a*d;
  var sum_y=b*c;
  max_x=max_num(sum_x,sum_y);
  max_y=max_num(sum_x,sum_y);
  var N=fenshu(sum_x,sum_y,max_x);
  return a+"/"+b+"÷"+c+"/"+d+"="+N;
  break;
  }
  }
 }
 function count(a,b){
  var Arr = ["+","-","*","/"]; 
  var n = GetRandomNum(0,3);
  switch(Arr[n]){
  case "+":{
  var sum=a+b;
  return a+"+"+b+"="+sum;
  break;
  }
  case "-":{
  var sum=a-b;
  while(sum<0){
   var a = GetRandomNum(1,30);
   var b = GetRandomNum(1,30);
   var sum=a-b;
  }
  return a+"-"+b+"="+sum;
  break;
  }
  case "*":{
  var sum=a*b;
  return a+"*"+b+"="+sum;
  break;
  }
  case "/":{
  var sum=a/b;
  while(a%b!==0){
   var max_x=max_num(a,b);
   var N=fenshu(a,b,max_x);
   return a+"÷"+b+"="+N;
  }
  return a+"÷"+b+"="+sum;
  break;
  }
  }
 }
 function pl_f() {
 var son_a = GetRandomNum(1,30); 
 var par_b = GetRandomNum(1,30);
 var son_c = GetRandomNum(1,30); 
 var par_d = GetRandomNum(1,30);
 var suma=f_count(son_a,par_b,son_c,par_d);
 return suma;
 }
 function pl() {
  var a = GetRandomNum(1,30); 
  var b = GetRandomNum(1,30);
  var sumb=count(a,b);
  return sumb;
 }
 function play_all() {
  for (i = 1; i <=30; i++) {
  var a = GetRandomNum(0,1);
  document.getElementById("text").innerHTML+=("<br>"+"第"+i+"题：");
  switch (a) {
   case 0:
   var A=pl();
   var strs = A.split("=");
   document.getElementById("text").innerHTML+=(strs[0]+"="+"<br>");
   document.getElementById("text2").innerHTML+=("<br>"+"第"+i+"题答案："+strs[1]);
   break;
   case 1:
   var B=pl_f();
   var strs = B.split("=");
   document.getElementById("text").innerHTML+=(strs[0]+"="+"<br>");
   document.getElementById("text2").innerHTML+=("<br>"+"第"+i+"题答案："+strs[1]);
   break;
  }
  }
 }
 </script>
</html>

以上就是本文的全部内容，希望对大家的学习有所帮助，也希望大家多多支持路饭。

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