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Код: Выделить всё

#include <stdio.h>
#include <stdlib.h>
#include <assert.h>
 
typedef struct NODE {
    int value;
    struct NODE * next;
} node_t;
 
void push(node_t ** pRing, int nValue) {
    node_t * pNode = malloc(sizeof(node_t));
    assert ( pNode );
    pNode->value = nValue;
    if ( ! *pRing ) {
        pNode->next = pNode;
        *pRing = pNode;
    }
    else {
        pNode->next = (*pRing)->next;
        (*pRing)->next = pNode;
        *pRing = pNode;
    }
}
 
void rotate(node_t ** pRing, int steps) {
    assert ( *pRing && steps > 0 );
    while ( steps-- )
        *pRing = (*pRing)->next;
}
 
 
int top(const node_t * ring) {
    return ring->value;
}
 
int is_empty(const node_t * ring) {
    return ( ! ring );
}
 
int shift(node_t ** pRing) {
    int ret;
    assert ( *pRing );
    ret = (*pRing)->value;
 
    if ( (*pRing)->next == *pRing ) {
        free(*pRing);
        *pRing = NULL;
    }
    else {
        node_t * pPrev = (*pRing)->next;
        while ( pPrev->next != *pRing )
            pPrev = pPrev->next;
        pPrev->next = (*pRing)->next;
        free(*pRing);
        *pRing = pPrev->next;
    }
 
    return ret;
}

node_t * find(const node_t * ring, const int value) {
    const node_t * current = ring;
    do {
        if ( current->value == value )
            return (node_t*)current;
        current = current->next;
    } while ( current != ring );
    return NULL;
}

int main(void) {
    node_t * ring = NULL;
    int count, i, value;
    
    printf("Number of elements: ");
    assert ( scanf("%d", &count) == 1 && count > 0 );
    for ( i = 0; i < count; ++i ) {
        printf("Value #%d: ", i + 1);
        assert( scanf("%d", &value) == 1 );
        push(&ring, value);
    }
    
    rotate(&ring, 1);
    
    while ( ! is_empty(ring) )
        printf("%d ", shift(&ring));
 
    return 0;
}