Question

File input.txt contains 100,000 numbers separated by new line. Do the following: Write a C++ program to compute the summation of these 100,000 numbers using single thread Write a C++ program to compute the summation of these 100,000 numbers using 10 threads, meaning each thread compute 10,000 summations and the main thread sum the result of the 10 threads. Using the time syscall to compare the time spent for 1.1 and 1.2 1.1 1.2 1.3 Turn Ins Source code of two programs and a short report on to answer the following question: 1. What is the run time for 1.1? 2. What is the run time for 1.2? 3. Is there a run time difference and why?

input.txt link

https://learn-us-east-1-prod-fleet01-xythos.s3.us-east-1.amazonaws.com/5b5739b6d55fd/3861301?response-content-disposition=inline%3B%20filename%2A%3DUTF-8%27%27input%25281%2529.txt&response-content-type=text%2Fplain&X-Amz-Algorithm=AWS4-HMAC-SHA256&X-Amz-Date=20190312T204757Z&X-Amz-SignedHeaders=host&X-Amz-Expires=21600&X-Amz-Credential=AKIAIBGJ7RCS23L3LEJQ%2F20190312%2Fus-east-1%2Fs3%2Faws4_request&X-Amz-Signature=2d90d87f5d1990624546690af1edaaa2bab9e6c32cc53ced578ca44c0d15d214

Answer 1

The following code can be used to compute the summation of these 100,000 numbers using single thread

#include <chrono.h>
#include <stdlib.h>
#include <iostream.h>
#include<conio.h>
#include <iomanip.h>
//#include <string.h>
#include <fstream.h>

//using namespace std;

int main(int argc, char * argv[])
{
ifstream myfile;
myfile.open("Input.txt");
auto st=high_resolution_clock::now();
float sum = 0;
float a=0;
//myfile >> a;
int i=0;
while (!myfile.fail())
{
   myfile >> a;
   sum+=a;
}

myfile.close();
auto stp=high_resolution_clock::now();
auto dur=duration_cast<microseconds>(stp-st);
cout<<"Total time taken ="<<dur.count()<<"ms"<<endl;// displaying time taken
cout<<"Sum of integers: "<<sum<<endl; // displaying results

getch();
return 0;
}

NOTE: The given url of .txt file was not working. Thus, demo file was considered.