Cod sursa(job #2602161)

Utilizator Alex_tz307Lorintz Alexandru Alex_tz307 Data 16 aprilie 2020 01:38:23
Problema Problema Damelor Scor 90
Compilator cpp-64 Status done
Runda Arhiva educationala Marime 3.43 kb
#include <bits/stdc++.h>

using namespace std;

class InParser
{
private:
    FILE *fin;
    char *buff;
    int sp;

    char read_ch()
    {
        ++sp;
        if(sp==4096)
        {
            sp=0;
            fread(buff,1,4096,fin);
        }
        return buff[sp];
    }

public:
    InParser(const char* nume)
    {
        fin=fopen(nume,"r");
        buff=new char[4096]();
        sp=4095;
    }

    InParser& operator >> (int &n)
    {
        char c;
        while(!isdigit(c=read_ch())&&c!='-');
        int sgn=1;
        if (c=='-')
        {
            n=0;
            sgn=-1;
        }
        else
        {
            n=c-'0';
        }
        while(isdigit(c=read_ch()))
        {
            n=10*n+c-'0';
        }
        n*=sgn;
        return *this;
    }

    InParser& operator >> (long long &n)
    {
        char c;
        n=0;
        while(!isdigit(c=read_ch())&&c!='-');
        long long sgn=1;
        if(c=='-')
        {
            n=0;
            sgn=-1;
        }
        else
        {
            n=c-'0';
        }
        while(isdigit(c=read_ch()))
        {
            n=10*n+c-'0';
        }
        n*=sgn;
        return *this;
    }
};

class OutParser
{
private:
    FILE *fout;
    char *buff;
    int sp;

    void write_ch(char ch)
    {
        if(sp==50000)
        {
            fwrite(buff,1,50000,fout);
            sp=0;
            buff[sp++]=ch;
        }
        else
        {
            buff[sp++]=ch;
        }
    }

public:
    OutParser(const char* name)
    {
        fout=fopen(name,"w");
        buff=new char[50000]();
        sp=0;
    }
    ~OutParser()
    {
        fwrite(buff,1,sp,fout);
        fclose(fout);
    }

    OutParser& operator <<(int vu32)
    {
        if(vu32<=9)
        {
            write_ch(vu32+'0');
        }
        else
        {
            (*this) <<(vu32/10);
            write_ch(vu32%10+'0');
        }
        return *this;
    }

    OutParser& operator <<(long long vu64)
    {
        if(vu64<=9)
        {
            write_ch(vu64+'0');
        }
        else
        {
            (*this) <<(vu64/10);
            write_ch(vu64%10+'0');
        }
        return *this;
    }

    OutParser& operator <<(char ch)
    {
        write_ch(ch);
        return *this;
    }
    OutParser& operator <<(const char *ch)
    {
        while(*ch)
        {
            write_ch(*ch);
            ++ch;
        }
        return *this;
    }
};
InParser f("damesah.in");
OutParser g("damesah.out");

int x[16], solutie[16];

void tiparesteSolutie(int n)
{
	for (int i = 1; i <= n; i++) g << x[i] << " ";
	g << '\n';
}

bool eValid(int k)
{
	for (int i = 1; i < k; i++)
    if ((x[k] == x[i]) || (k - i == abs(x[k] - x[i]))) return false;
	return true;
}

int backtrack(int n)
{
	int eSolutie, k;
	k = 1;
	x[k] = 0;
	int nrSolutii = 0;
	int prima = 1;
	while (k > 0)
    {
		eSolutie = 0;
		while ((x[k] < n) && (!eSolutie))
        {
			x[k]++;
			eSolutie = eValid(k);
		}
		if (!eSolutie) k--;
		else
		{
			if (k == n)
			{
				if (prima)
				{
					tiparesteSolutie(n);
					prima = 0;
				}
				nrSolutii++;
			}
			else
			{
				k++;
				x[k] = 0;
			}
		}
	}
	return nrSolutii;
}

int main()
{
	int n;
	f >> n;
	int nrSolutii = backtrack(n);
	g << nrSolutii;
	return 0;
}