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Код: Выделить всё

int size = rand() % 500;

// Allocating new array in the heap
int* p = new int [size];

// Here we work with p as with ordinal array
for (int i = 0; i < size; ++i)
{
   p[i] = i;
}

// Don't forget to free the memory
delete [] p;

Код: Выделить всё

/* Задача: Составить программу для вычисления степеней чисел вида  an, если  a > MaxInt,  n > 10. */

#include <iostream>
#include <conio.h>

#define int_max 10000
void perevorot(int mas[], int x)
{
	int tmp,i,j;
	j=x;
	for(i=0;i<j;i++){
		j--;
		tmp=mas[j];
		mas[j]=mas[i];
		mas[i]=tmp;
	}
}
int addsum(int outmas[],int x,int mas[], int z)
{
	perevorot(mas,z);
	perevorot(outmas,x);
	int overbit=0,i=0,j;
	j=z;
	j--;
	while(i<j){
		outmas[i]+=mas[i];
		outmas[i]+=overbit;
		if (outmas[i]>9) {
			outmas[i]-=10;
			overbit=1;
		} else overbit=0;
        i++;
	}
	outmas[i]+=mas[i];
	outmas[i]+=overbit;
	if (outmas[i]>9){
		outmas[i]-=10;
		i++;
		outmas[i]+=1;
	}
	i++;
	perevorot(outmas,i);
	perevorot(mas,z);
	return i;
}

int umnoj(int outmas[],int x,int tmas1[], int z1, int tmas2[], int z2)
{   
	int i,q=0;
	for(i=0;i<int_max;i++) outmas[i]=0;
	int mas1[int_max],mas2[int_max];
	for(i=0;i<int_max;i++) mas1[i]=mas2[i]=0;
	for(i=0;i<int_max;i++) {
		mas1[i]=tmas1[i];
		mas2[i]=tmas2[i];
	}
	perevorot(mas1,z1);
	perevorot(mas2,z2);
	int j=0,st=0,razryad=0,nommas=0;
	int tmp[int_max];
	for(i=0;i<int_max;i++) tmp[i]=0;
	for(razryad=0;razryad<z2;razryad++){
			nommas=razryad;
		for(j=0;j<z1;j++){
						//перебор
			tmp[nommas]+=(mas1[j]*mas2[razryad])%10;
			nommas++;
			tmp[nommas]+=(mas1[j]*mas2[razryad])/10;

		}
		if ((mas1[j]*mas2[razryad])>9||z1==1) nommas++;
		perevorot(tmp,nommas);
		q=addsum(outmas,q,tmp,nommas);
		for(st=0;st<int_max;st++)
			tmp[st]=0;
	}
	return q;
}
int stepen(int outmas[],int n,int inmas[], int x,int st)
{	
	int i,j;
	if(st==0) {
		for(i=0;i<int_max;i++) outmas[i]=0;
		outmas[0]=1;
		return 1;
	}else if(st==1){
		for(i=0;i<int_max;i++) outmas[i]=inmas[i];
		return x;
	}
	int a[int_max];
	n=umnoj(outmas,n,inmas,x,inmas,x);
	for(i=3;i<=st;i++){
		for(j=0;j<int_max;j++) a[j]=outmas[j];
		n=umnoj(outmas,n,a,n,inmas,x);
	}
	return n;
}
int vvodchisla(int mas[])
{
	using namespace std;
	char c=0;
	int i,top=0;
	for(i=0;i<int_max;i++) mas[i]=0;
	while (c!=13){
		c=getch();
		if(c<='9'&&c>='0') {
			if(top==int_max){
				cout << "bolshe nelza!" << endl;
				continue;
			}
			cout << c;
			mas[top]=c-'0';
			top++;
		}
		if(c=='\b'){
			cout << '\b' << ' ' << '\b';
			top--;
		}
	}
	return top;
}
void main()
{
	using namespace std;
	int indigit[int_max];
	int outdigit[int_max];
	int i,n=0,top=0,st;
	cout << "vvedite chislo \n";
	top=vvodchisla(indigit);
	cout << "\nv kakuye stepen vozvodim?\n";
	cin >> st;
	cout << "\n+++++++++++\n";
	n=stepen(outdigit,n,indigit,top,st);
	for(i=0;i<n;i++)
		cout << outdigit[i];
	getch();
}

Код: Выделить всё

int size = rand() % 500;
int* p = new int [size];

// Here we work with p
...

// Let's image situation that we need to reallocate memory
// Function GetNewSize is our one and it returns new needed memory size

int new_size = GetNewSize();
int min_size = size < new_size ? size : new_size;

// Allocate new memory segment
int* new_p = new int [new_size];
// Initialize it with zeros
memset(new_p, 0, new_size * sizeof(int));
// Copy old data to new memory segment
// If new segment is less then old - tail data will be ignored
memcpy(new_p, p, min_size);

// Deleting old memory segment
delete [] p;
// Now p points to the new segment of new required size
p = new_p;

// Here we work with p
// ...

// Dont forget to free new memory segment
delete [] p;