#include<bits/stdc++.h>
#include<sstream>
using namespace std;
int main()
{
    int n;
    cin>>n;
    //string a[1005]={};
    for(int i=0;i<n;i++)
    {
        int b;
        cin>>b;
        string c1,c2;
        cin>>c1;
        char d;
        cin>>d;
        cin>>d;
        cin>>c2;
        cout<<b<<" "<<c1<<" = ";
        if(c1=="m"&&c2=="mm")
        {
            cout<<b*1000;
        }
        else if(c1=="km"&&c2=="mm")
        {
            cout<<b*1000000;
        }
        else if(c1=="km"&&c2=="m")
        {
            cout<<b*1000;
        }
        else if(c1=="g"&&c2=="mg")
        {
            cout<<b*1000;
        }
        else if(c1=="kg"&&c2=="mg")
        {
            cout<<b*1000000;
        }
        else if(c1=="kg"&&c2=="g")
        {
            cout<<b*1000;
        }
        cout<<" "<<c2<<"\n";
    }
}

C++ :

#include <bits/stdc++.h>
using namespace std;

int main(){
	int n;
	cin>>n;
	for(int i1=0;i1<n;i1++){
	int a;
	string a1,b1,aaaa;
	cin>>a>>a1>>aaaa>>aaaa>>b1;
	int i=a;
	if(a1=="m") a*=1000;
	else if(a1=="km"){
		if(b1=="m")a*=1000;
		else a*=1000000;
	}
	else if(a1=="g") a*=1000;
	else if(a1=="kg"){
		if(b1=="g")a*=1000;
		else a*=1000000;
	}	
	cout<<i<<' '<<a1<<" = "<<a<<' '<<b1<<endl;
	}
}