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COMPUTING LCM OF TWO NUMBERS

chofs (49)
hey guys pleassssssseeeeeeeee help...am trying to find the LCM between numbers a and b...so i made a loop of those two values multiplying by "i" as depicted from the code...the LCM of the two values is found when sum==sum2...in my text file a=5 and b=8 hence the LCM of both numbers is 40...so the loop runs if it hits 40 it shud break but its not breaking dont know y coz i used a break statement for those conditions when sum==sum2.......please can sum1 assist me..thanx in advance

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 #include <iostream>
#include <vector>
#include <fstream>

using namespace std;

void getvaluesfromfile(vector<int>&A,vector<int>&B)
{
    double a=0;
    double b=0;

    ifstream infile("indata.txt");

    while(infile>>a>>b)
    {
        A.push_back(a);
        B.push_back(b);
    }
}

void calculategcd(vector<int>A,vector<int>B)
{
    int sum=0;
    int sum2=0;
    for(int i=1;i<100;i++)
    {
        sum=A[0]*i;
        sum2=B[0]*i;

        if(sum==sum2)
            break;

            cout<<sum<<"   "<<sum2<<endl;

    }

}

int main()
{
    vector<int> A;
    vector<int> B;

    getvaluesfromfile(A,B);
    calculategcd(A,B);

}
Last edited on
MiiNiPaa (8886)
Are you sure that you need LCM? Your function has GCD in its name.

Your sum and sum2 will never be equal if A[0] and B[0] are not equal. Basic math:
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X×i ? Y×i  |i∈N, X != Y  |Divide dy i
  X ? Y
  X != Y


Anyway formula for calculating LCM is following: LCM(x, y) = (|x·y|) / GCD(x,y)
chofs (49)
thanxxxxxxxxxxxxxx a billion it works:)
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