Dev 能运行啊 。 怎么编译失败了 ？

#include<bits/stdc++.h>
using namespace std;
int main()
{
	int y1,y2,x1,x2,km,kz,bm,bz;
	cin>>x1>>y1>>x2>>y2;
	km=x2-x1;
	kz=y2-y1;
	bm=x1-x2;
	bz=y2*x1-y1*x2;
	if(km!=0&&kz!=0)
	{
		if(km%kz==0)
		{
			km/=kz;
			kz=1;
		}
		if(kz%km==0)
		{
			kz/=km;
			km=1;
		}
	} 
	//cout <<km<<" "<<kz<<" "<<bm<<" "<<bz<<endl;
	cout <<"y=";
	if((kz<0)+(km<0)==1)
		cout <<"-";
	if(abs(kz)!=abs(km)&&kz!=0&&km!=0)
		cout <<abs(kz);
	if(abs(kz)!=abs(km)&&kz!=0&&km!=0&&km!=1)
		cout <<"/"<<abs(km)<<"*";
	if(kz!=0&&km!=0)
		cout <<"x";
	if(kz!=0&&km!=0&&bz!=0&&bm!=0&&((bz<0)+(bm<0))%2==0)
		cout <<"+";
	if(((bz<0)+(bm<0))==1&&kz!=0&&km!=0&&bz!=0&&bm!=0)
		cout <"-";
	if(abs(bz)==abs(bm)&&bz!=0)
		cout <<"1";
	if(bz!=0&&bm!=0&&abs(bz)!=abs(bm))
		cout <<abs(bz);
	if(bz!=0&&bm!=0&&abs(bz)!=abs(bm)&&bm!=1)
		cout <<"/"<<abs(bm);
	return 0;
}