2_shift_left

Posted 2023-03-01 taxue505

//0 1 2 3 4 5 6 7
//1 2 3 4 5 6 7 0
//2 3 4 5 6 7 0 1
#include<iostream>
#include<vector>

using namespace std;

void reverse_arr(vector<int>&vec,int start,int end)

    for(;start<end;start++,end--)
    
        swap(vec[start],vec[end]);
    

void shift_left(vector<int>&vec,int k)

    int len=vec.size();  
    k=k%len;
    reverse_arr(vec,0,k-1);
    reverse_arr(vec,k,len-1);
    reverse_arr(vec,0,len-1);



int main()

    int arr[8]=0,1,2,3,4,5,6,7;
    vector<int> vec(arr,arr+8);
    
    shift_left(vec,3);
    
    for(int i=0;i<vec.size();i++)
        cout<<vec[i];
    cout<<endl;


//
//g++ shift_left.cc -o shift_left
//./shift_left