Example: C Program to Rearrange Positive and Negative Numbers in Array

// C Program to Rearrange Positive and Negative Numbers in Array
#include <stdio.h>

void alterNumber(int *arru, int i, int j) {
    int temp = arru[i];
    arru[i] = arru[j];
    arru[j] = temp;
}

void splitNegativeElement(int *arru, int size) {
    int temp, left = 0, right = size - 1;
    while (right > left) {
        while (arru[left] < 0)
            left++;

        while (arru[right] > 0)
            right--;

        if (left < right) {
            alterNumber(arru, left, right);
        }
    }
}

// It's the driver function of
// array element arrangements
void reArrangeNumbers(int *arru, int size) {
    int i, j;
    splitNegativeElement(arru, size);

    for (i = 0; arru[i] < 0; i++);
    for (j = 1; (j < i) && (arru[j] < 0); j += 2) {
        alterNumber(arru, i, j);
        i++;
    }
    return;
}

int main() {
    int i, arru[] = { -14, 18, -15, -16, 15, 29, 27, 21, -21, -11, 29 };
    int arru_size = sizeof(arru) / sizeof(arru[0]);

    // It's the array iteration
    printf("------This is the given array before arrangement------\n\t");
    for (i = 0; i < arru_size; i++) {
        printf("%d,  ", arru[i]);
    }
    printf("\n\n");

    // It's the array iteration
    printf("------This is the Re-arranged array------\n\t");
    // This will re-arrange the given array
    reArrangeNumbers(arru, 10);
    for (i = 0; i < 11; i++) {
        printf("%d ", arru[i]);
    }
    printf("\n");
    return 0;
}