After-school experiment arithmetic

First, Function introduction

1. Can achieve any two integers within 100 and the true fraction of the mixed arithmetic, random number with time changes do not repeat, and take into account the meiosis is greater than the meiosis and the divisor can not be zero, you can automatically output 20 different formulas.

Second, the idea of programming

1. First write the random number function
2. Generate two random numbers, call a random number function, a true fraction and an integer, and use a random number to take the remainder to combine the two random numbers.
3. Using the random number of the remainder to implement the selection of operators, where division to ensure that the divisor is not zero, subtraction to ensure that the minuend greater than the meiosis, using the corresponding operator and two random numbers of the formula to calculate the results.
4. Use the loop to achieve the output of 20 arithmetic formulas.

Third, the experimental code

Haoying 2016.3.3 Letter 1301-2 class 20132919
Arithmetic Small Program
#include <iostream>
#include <stdlib.h>
#include <time.h>
using namespace Std;
int main ()
{
Double n[4];
int edg,choose,i,next;
Char Mark;
Srand ((int) time (NULL));//Transform random number
for (next=0;next<20;next++)//Set 20 lanes per day arithmetic
{
for (i=0;i<2;i++)
{
Edg= (rand ()%100)%2;
if (edg==0)
N[i]=rand ()%100;//random number range "0,100"
Else
N[i]=rand ()%100/100.0;//random true fraction
}
Choose= (rand ()%100)%4;
if (choose==0)
{
N[2]=N[0]+N[1];
mark= ' + ';
}
else if (choose==1)
{
if (N[0]>n[1])
{
N[2]=N[0]-N[1];
mark= '-';
}
Else
{
N[3]=N[0];
N[0]=N[1];
n[1]=n[3];//make the meiosis greater than the meiosis
N[2]=N[0]-N[1];
mark= '-';
}
}
else if (choose==2)
{
N[2]=N[0]*N[1];
mark= ' * ';
}
else if (choose==3)
{
while (n[1]==0)//guaranteed divisor greater than 0
{
Edg= (rand ()%100)%2;
if (edg==0)
N[1]=rand ()%100;//random number range "0,100"
Else
N[1]=rand ()%100/100.0;//random true fraction
}
N[2]=N[0]/N[1];
mark= '/';
}
cout<<n[0]<<mark<<n[1]<< "=" <<n[2]<<endl;//Display the formula
}
return 0;
}

Iv. Results of operation

After-school experiment arithmetic