exista

nr maxim:
int nrmaxim (int n)

{

   int m=n,max=n,nrc=1,c,f=1;

   while (m>9) { ++nrc; m/=10; f*=10;}

   for (int i=1;i<nrc;++i) {

     c=n/f; n=n%f*10+c;

     if (n>max) max=n;

   }

   return max;

}
phi:
int Phi(int n)
{
    int r = n , d = 2;
    while(n > 1)
    {
        if(n % d == 0)
        {
            r = r / d * (d - 1);
            while(n % d == 0)
                n /= d;
        }
        d ++;
        if(d * d > n)
            d = n;
    }
    return r;
}
factorial2:
int det(int n)
{
  int p = 1 , k = 1;
  while(p < n) k ++ , p *= k;
  if(p == n) return p;
  int t = p / k;
  if(n - t <= p - n) return t;
  else return p;
}
numere norocoase:
int norocoase(int a,int b)
{
int c=0,i;
if (a%2==0)
    for (i=a+1;i<=b;i+=2)
        c++;
    else
        for (i=a;i<=b;i+=2)
            c++;
return c;
}
zerofact:
int nz (int n)
{
    int k=0;
    for (int i=5; i<=n; i*=5)
    {
        k+=n/i;
    }
    return k;
}
poz:
int poz(int x1, int y1, int l1, int i1, int x2, int y2, int l2, int i2)

{

   int r;

   if (x1==x2 && y1==y2 && l1==l2 && i1==i2) r=1;

   else

   {

      if (x1+l1<x2 || y1+i1<y2 || x2+l2<x1 || y2+i2<y1 ) r=2;

      else

      {

         if ((x1<x2 && y1<y2 && x1+l1>x2+l2 && y1+i1>y2+i2) || (x2<x1 && y2<y1 && x2+l2>x1+l1 && y2+i2>y1+i1)) r=0;

         else

          r=3;

      }

   }

   return r;

}
resturi1:
#include <iostream>

using namespace std;

int resturi(int n, int x, int y, int r) {

   int nr = 0, i;
   if (x > y) {

   int temp = y;

   y = x;

   x = temp;

   }

   for (i = r; i <= n; i += y) {

       if (i % x == r)

           nr++;

   }

   return nr;

}
diofantic:
int diofantic(int n, int s[50001], int a,long long b,int c)
{
int k=0;int i=1; int j=n;
while(i<=n && j>0)
{
if(a*s[i]*s[i]+b*s[j]*s[j]==c )
{
k++;
i++;
}
if(a*s[i]*s[i]+b*s[j]*s[j]<c)
i++;
if(a*s[i]*s[i]+b*s[j]*s[j]>c)
j--;
}
return k;
}
FRadical:
void FRadical (int n, int &x, int &y)
{
    x = 1;
    y = 1;
    int d = 2;
    while (n > 1) {

        int e = 0;
        while (n % d == 0) {

            e ++;
            n = n / d;
    }
        if (e) {

            if (e % 2 == 0)
                x = x * pow(d, e / 2);
            else {

                y = y * d;
                e --;
                if (e)
                    x = x * pow (d, e / 2);
            }
        }
        d ++;
    }

}
FInserare:
int inserare (int &n) {

    int x, v[15], k = 1;
    x = n;
    while (x)
    {
        v[k++] = x % 10;
        x = x / 10;
    }
    for (int i = k - 1; i >= 2; i--)
    {
        x = x * 10 + v[i];
        x = x * 10 + abs(v[i] - v[i-1]);
    }
    x = x * 10 + v[1];
    n = x;
    return n;
}
Impare_bac:
void Impare (int &n) {
    int aux, uc, p = 1;
    aux = n;
    while (aux > 0) {
        uc = aux % 10;
    if (uc % 2 != 0)
          n -= p;
        p *= 10;
        aux /= 10; }
}
maxprime:
int prim(int nr)
{
    int prim=1;
    if(nr==0 || nr==1)
        prim=0;
    if(nr>2 && nr%2==0)
        prim=0;
    for(int d=3;d*d<=nr;d+=2)
        if(nr%d==0)
            prim=0;
    return prim;
}
void sub(int n,int &a,int &b)
{
    bool stop=false,a1=false,b1=false;
    n--;
    while(n && stop==false)
    {
        if(prim(n))
            if(a1==false)
                a=n,a1=true;
            else
                b=n,b1=true;
        if(a1==true && b1==true)
            stop=1;
        n--;
    }
}
interval factorial:
void interval(int n,int &a,int &b)
{
    int f=1;
    for(int i=2;i<n;i++)
        f=f*i;
    a=f+1;
    b=f*n*(n+1)-1; }