CODEWITHSUNDEEP
carrays
EGTech
EGTech

Reputation: 23

C Program - Shifting Elements in an array

"Write a program that allows a user to input an integer for the size of an array. Using Malloc is recommended. Randomly generate an integer for each element of the array. Next, creating a funcion to rotate the array. Rotation of the array means that each element is shifted right or left by one index, and the last element of the array is also moved to the first place"

Example: 31 83 91

Which direction to shift and how many times?- Left

How many times would you like to shift? 2

End Result: 91 31 83

Currently my code. It's not shifting. 

#include <stdio.h>
#include <stdlib.h>

int main(){

int i, temp, swapped;
int SlotNumber;
int *ptr;
char direction;
int ShiftAmount;

printf("How many slots would you like in your array?\n");
scanf("%d", &SlotNumber);
for(i=0;i<SlotNumber;i++){
    printf("%d \t", rand());
}
ptr = (int *)malloc(SlotNumber*sizeof(int));

printf("\nWhich direction would you like to shift it to? R/L?\n");
scanf(" %c", &direction);
printf("\nHow many times would you like to shift?\n");
scanf("%d", &ShiftAmount);

if((direction=='R')||(direction=='r')){
    while(1){
        swapped = 0;
        for(i=0;i<ptr+1;i++){
            if(ptr[1]>ptr[i+ShiftAmount]){
                int temp = ptr[i];
                ptr[i] = ptr[i+ShiftAmount];
                ptr[i+ShiftAmount] =temp;
                swapped = 1;
            }
        }
        if(swapped == 0);
        break;
    }
}
printf("\nNewList\n");
for(i=0;i<ptr;i++){
    printf("%d \t",ptr[i]);
}

return 0;
}

Upvotes: 1

Views: 3744

Answers (1)

Giorgi Moniava
Giorgi Moniava

Reputation: 28654

There were few problems with your code. Here is improved solution with left shift, right shift I leave to you.

#include <stdio.h>
#include <stdlib.h>
#include <time.h>


int main()
{

    int i, j;
    int SlotNumber;
    int *ptr;
    int ShiftAmount;
    int temp;

    srand(time(NULL));

    printf("How many slots would you like in your array?\n");
    scanf("%d", &SlotNumber);

    ptr = malloc(SlotNumber*sizeof(int));

    // Fill array with random numbers
    for(i=0;i < SlotNumber; i++)
    {
        ptr[i]=rand();
        printf("%d \t",ptr[i]);

    }

    printf("\nHow many times would you like to shift?\n");
    scanf("%d", &ShiftAmount);


    for(i=0; i < ShiftAmount; i++)
    {
        temp = ptr[0];
        for(j=0;j < SlotNumber - 1;j++)
        {
            ptr[j] = ptr[j+1];
        }
        ptr[SlotNumber - 1]=temp;
    }

    printf("\nNewList\n");
    for(i=0; i < SlotNumber; i++)
    {
        printf("%d \t",ptr[i]);
    }

    free(ptr);

    return 0;
}

Upvotes: 1

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