Software engineering with small work-random arithmetic (c + +)

First, design ideas:

1. The main part of the program is the loop output, the number of topics by the user input;

2. Three integer variable +rand function to implement the random number arithmetic, one variable represents subtraction, and the other two are used as operands;

3. User experience: The topic is divided into three columns, neat and tidy spacing, and will not show a divisor of 0.

Since a winter vacation did not touch the programming, the biggest difficulty for me is not knowing the usage of the RAND function and the header file where it resides. I adjusted the page again after the basic ability was realized.  Added Srand ((unsigned) time (NULL)); 。 Because only the RAND function is used, the random number generated by each run of the program computer is fixed.

Second, the source code

#include "stdafx.h"

#include "iostream.h"

#include "Stdlib.h"

#include "time.h"

int main (int argc, char* argv[])

{

int a,b,c,n=1; A represents the operation symbol, b c is two numbers, n indicates the number of the question.

Srand ((unsigned) time (NULL)); The Srand () function produces a random seed that starts at the current time

cout<< "Please enter the number of question:";

cin>>n;

for (int i=1;i<=n;i++)

{

A=rand ()%4;

B=rand ()%100; b c is a two random integer within 100

C=rand ()%100;

cout<< "(" <<i<< ")" <<b;

Switch (a)

{

Case 1:cout<< "+" <<c<< "=\t\t";

Case 2:cout<< "-" <<c<< "=\t\t";

Case 3:cout<< "*" <<c<< "=\t\t";

Case 0:if (c==0) {i--;break;}

cout<< "/" <<c<< "=\t\t";

default:cout<< "+" <<c<< "=\t\t";

}

if (i%3==0)

cout<<endl;

}

cout<<endl;

return 0;

}

Iii. Results of operation

Software engineering with small work-random arithmetic (c + +)