Question

can someone edit my c++ code where it will output to a file. I am currently using xcode.

#include <iostream>

#include <cctype>

#include <cstring>

#include <fstream>

using namespace std;

bool inputNum(int [],int&,istream&);

void multiply(int[],int,int[],int,int[],int&);

void print(int[],int,int,int);

int main()

{ifstream input;

int num1[35],num2[35],len1,len2,num3[60],len3=10,i;

input.open("multiplyV2.txt"); //open file

if(input.fail()) //is it ok?

{ cout<<"file did not open please check it\n";

system("pause");

return 1;

}

  

while(inputNum(num1,len1,input))

{inputNum(num2,len2,input);

multiply(num1,len1,num2,len2,num3,len3);

print(num1,len1,len3,1);

print(num2,len2,len3,2);

for(i=0;i<len3;i++)

cout<<"-";

cout<<endl;

print(num3,len3,len3,1);

//cout<<len1<<" "<<len2<<" "<<len3<<endl;

cout<<endl;

  

}

system("pause");

}

void print(int num[],int len, int maxlen,int n)

{int i,count;

count=maxlen-len;

if(n==2)

count--;

for(i=0;i<count;i++)

cout<<" ";

if(n==2)

cout<<"x";

for(i=len-1;i>=0;i--)

cout<<num[i];

cout<<endl;

}

void multiply(int num1[],int len1,int num2[],int len2,int num3[],int& len3)

{int i,j,tmp ;

for(i=0;i<60; i++)

num3[i]=0;

for(i=0;i<len2;i++)

{ len3=i;

for(j=0;j<len1;j++)

{tmp=num1[j]*num2[i];

num3[len3]=num3[len3]+tmp;

num3[len3+1]=num3[len3+1]+num3[len3]/10;

num3[len3]%=10;

len3++;

}

}

if(num3[len3]!=0)

len3++;

}

bool inputNum(int integer[],int& len,istream& file)

{string in;

int j,k;

for (len=0;len<35;len++ )

integer[len]=0;

len=35-1;

file>>in;

if(!file)

return false;

for(len=0;in[len]!='\0';len++);

k=0;

for(j=len-1;j>=0;j--)

integer[j]=in[k++]-48;

return true;

}

Answer 1

Check it out I've edited your program now all the output generated from this program will be saved in a file named OutputFile.txt.

There is not much task in performing this task all you need to do is

ofstream myfile; /*your file
  myfile.open ("example.txt"); here the file will open and after this statement every output in the program will be written in this file. */

myfile.close(); // When the task is done and your program is about to return please close the output file.

Your program starts from here

#include <iostream>

#include <cctype>

#include <cstring>

#include <fstream>

using namespace std;

bool inputNum(int [],int&,istream&);

void multiply(int[],int,int[],int,int[],int&);

void print(int[],int,int,int);

int main()

{

ofstream myfile;
  myfile.open ("OutputFile.txt");

ifstream input;

int num1[35],num2[35],len1,len2,num3[60],len3=10,i;

input.open("multiplyV2.txt"); //open file

if(input.fail()) //is it ok?

{ cout<<"file did not open please check it\n";

system("pause");

return 1;

}

  

while(inputNum(num1,len1,input))

{inputNum(num2,len2,input);

multiply(num1,len1,num2,len2,num3,len3);

print(num1,len1,len3,1);

print(num2,len2,len3,2);

for(i=0;i<len3;i++)

cout<<"-";

cout<<endl;

print(num3,len3,len3,1);

//cout<<len1<<" "<<len2<<" "<<len3<<endl;

cout<<endl;

  

}

system("pause");

}

void print(int num[],int len, int maxlen,int n)

{int i,count;

count=maxlen-len;

if(n==2)

count--;

for(i=0;i<count;i++)

cout<<" ";

if(n==2)

cout<<"x";

for(i=len-1;i>=0;i--)

cout<<num[i];

cout<<endl;

}

void multiply(int num1[],int len1,int num2[],int len2,int num3[],int& len3)

{int i,j,tmp ;

for(i=0;i<60; i++)

num3[i]=0;

for(i=0;i<len2;i++)

{ len3=i;

for(j=0;j<len1;j++)

{tmp=num1[j]*num2[i];

num3[len3]=num3[len3]+tmp;

num3[len3+1]=num3[len3+1]+num3[len3]/10;

num3[len3]%=10;

len3++;

}

}

if(num3[len3]!=0)

len3++;

}

bool inputNum(int integer[],int& len,istream& file)

{string in;

int j,k;

for (len=0;len<35;len++ )

integer[len]=0;

len=35-1;

file>>in;

if(!file)

return false;

for(len=0;in[len]!='\0';len++);

k=0;

for(j=len-1;j>=0;j--)

integer[j]=in[k++]-48;

 myfile.close();

return true;

}