How to move word in a circular motion in a string? - c++

Question

I have a string that contains X words (between each word there is a space) I have to move the words in a circular motion to the left according to the number that the user inserts. For example:
"hi my name is aviv and",
the user entered 2. "name is aviv and hi my" I'm looking for legality that repeats itself but I can not find.
Thanks for the guidance. Most importantly, I can not use built-in libraries
Update:
I see there are examples with libraries, I can not use any library.
So what I've done so far.
I wrote a function that gets a string and a number from the user, to move left.
Before sending the string to the function I try to calculate the number of characters I need to move.
My output is - "name is avivhi my"
Regarding the function:
When it gets a string without spaces it works great.
This is my code:
int main()
{
char str[] = "hi my name is aviv";
char str2[] = "hi my name is aviv";
int CountSpace = 0, CountWord = 0;
int Size = 18, flag = 0;
int MoveLeft, Index = 0;
for (int i = 0; str[i] != '\0'; i++)
{
if (str[i] == ' ')
{
CountSpace++;
}
}
CountWord = CountSpace + 1;//Understand how many words there are in a string.
cin >> MoveLeft;
if (MoveLeft >= CountWord)//
{
MoveLeft = (MoveLeft - ((MoveLeft / CountWord) * CountWord));//the size of movment;//To reduce the amount of moves if there is such a possibility
}
for (int i = Size - 1; i >= 0; i--)
{
if (str[i] == ' ')
{
flag++;
}
if (flag == MoveLeft)
{
Index = Size - 1 - (i + 1);//That's the amount of characters I have to move
break;
}
}
MoveLeft = Index;
//This code belongs to the function that accepts a string and the amount to move the characters
for (int i = 0; i < Size; i++)
{
if (i + MoveLeft < Size)
{
str[i] = str2[i + MoveLeft];
}
else
{
str[i] = str2[(i + MoveLeft) - Size];
}
}
cout << "Move Left: " << MoveLeft << endl << str << endl << str2 << endl;
return 0;
}

Answer 1

Here's a hint:
vector<string> words = Your_Code_To_Split_Input_Into_Words();
int count = words.size();
int shift = Your_Code_To_Read_Users_Input();
// print the sentence with the rotation specified by shift
for (int i = 0; i < count; i++)
{
int shifted_index = (i + shift) % count; // modulo math implements circular rotation
string spacing = (i == 0) ? "" : " "; // add a space before each word, except first word
cout << spacing << words[shifted_index];
}
cout << endl;

Answer 2

One possible answer, i highly recommend using vectors instead of regular arrays, it's easy and more dynamic, but i didn't use it because you said you can't use built-in libraries.
#include <iostream>
#include<string>
using namespace std;
int main() {
string a[10000];
int counter = 0;
string b = "hi my name is aviv and";
string temp = "";
int userNum = 2;
for(int i=0;i<b.length() ; i++){
if(b[i]!=' '){
temp+=b[i];
}
else if(b[i]==' ' && temp.length()){
a[counter]= temp;
temp = "";
counter++;
}
}
if(temp.length()){
a[counter] = temp;
}
for(int i=userNum;i<=counter+userNum;i++){
cout<<a[i%(counter+1)]<<endl;
}
}

Answer 3

If you can make use of std::rotate() from <algorithm>, this is much easy to do with that. Parse the words using std::stringstream and store to std::vector. Then apply the shif directly to the vector.
Sample Output: https://www.ideone.com/rSPhPR
#include <iostream>
#include <vector>
#include <algorithm>
#include <string>
#include <sstream>
int main()
{
std::vector<std::string> vec;
std::string str = "hi my name is aviv and";
std::string word;
std::stringstream sstr(str);
while(std::getline(sstr, word,' '))
vec.emplace_back(word);
int shift;
std::cout << "Enter the Shift: ";
std::cin >> shift;
std::rotate(vec.begin(), vec.begin() + shift, vec.end());
for(const auto& it: vec)
std::cout << it << " ";
return 0;
}

Answer 4

Here's a snippet :
#include <iostream>
#include <string>
#include <sstream>
using namespace std;
#define MaxWords 10
int main()
{
stringstream ss;
ss.str("hi my name is aviv and");
string str[MaxWords];
int i;
for (i =0; std::getline(ss, str[i],' ');i++ )
{
cout << str[i] << " ";
}
int n;
cout << "\nEnter pos to split : ";
cin >> n;
for (int j = n; j <= i; j++)
{
cout << str[j] << " ";
}
for (int j = 0; j < n; j++)
{
cout << str[j] << " ";
}
cout << endl;
return 0;
}
Output: