Cod sursa(job #428277)

Utilizator nandoLicker Nandor nando Data 29 martie 2010 09:01:45
Problema Ecuatie Scor 10
Compilator cpp Status done
Runda Arhiva de probleme Marime 1.71 kb
#include <cstdio>
#include <cstdlib>
#include <cmath>
#include <cstring>

#define MAX 1000000

long long sol[MAX][4],sol2[MAX][4],ns=0,ns2=0;
long long a,b,c,k,c1,c2,dd;
long long d,i;

void printeq(long long eq[]){
	printf("(");
	if(eq[0]!=1&&eq[0]!=-1){
		printf("%lld",eq[0]);
	}else if(eq[0]==-1){
		printf("-");
	}
	printf("x%c%lld)(",(eq[1]>0)?'+':'-',(eq[1]>0)?eq[1]:-eq[1]);
	if(eq[2]!=1&&eq[2]!=-1){
		printf("%lld",eq[2]);
	}else if(eq[2]==-1){
		printf("-");
	}
	printf("x%c%lld)\n",(eq[3]>0)?'+':'-',(eq[3]>0)?eq[3]:-eq[3]);
}

void addSol(long long s){
	if(((s*c1)%dd==0)&&(c2*a)%(dd*s)==0){
		sol[ns][0]=s;
		sol[ns][1]=-(c1*s)/dd;
		sol[ns][2]=a/s;
		sol[ns][3]=-(c2*a)/(s*dd);
		ns++;
	}
	if(((s*c2)%dd==0)&&(c1*a)%(dd*s)==0){
		sol[ns][0]=s;
		sol[ns][1]=-(c2*s)/dd;
		sol[ns][2]=a/s;
		sol[ns][3]=-(c1*a)/(s*dd);
		ns++;
	}
}
int comp(const void* p1,const void* p2){
	long long *v1=(long long*)p1,*v2=(long long*)p2;
	if(v1[0]-v2[0]==0){
		return v1[1]-v2[1];
	}else{
		return v1[0]-v2[0];
	}
}
int main(){

	FILE* fin=fopen("ecuatie.in","r");
	freopen("ecuatie.out","wt",stdout);
	fscanf(fin,"%lld %lld %lld %lld",&a,&b,&c,&k);
	d=b*b-4*a*c;
	i=(long long)sqrt(abs(d));
	if(i*i==d){
		c1=-b-i,c2=-b+i,dd=2*a;

		long long l=sqrt(abs(a));

		for(long long i=1;i<=l;i++){
			if(a%i==0){
				addSol(i),addSol(-i);
				addSol(a/i),addSol(-a/i);
			}
		}
		qsort(sol,ns,32,comp);
		for(int i=0;i<ns;i++){
			memcpy(sol2[ns2++],sol[i],32);
		//	printeq(sol2[ns2-1]);
			while(!memcmp(sol[i],sol[i+1],32)&&i<ns-1){
				i++;
			}
		}
		if(k<=ns2){
			printeq(sol2[k-1]);
		}else{
			printf("-1");
			return 0;
		}
	}else{
		printf("-1");
	}
	return 0;
}