Реверсированный список

#include <stdio.h>
#include <stdlib.h>
 
typedef struct NODE {
    int val;
    struct NODE * next;
} node_t;
 
int push(node_t ** top, int val){
    node_t * n;
    
    if ( ( n = (node_t*)malloc(sizeof(node_t)) ) == NULL )
        return 1;
    n->val = val;
    n->next = *top;
    *top = n;
    return 0;
}
 
int pop(node_t ** top, int * val){
    node_t * next;
    
    if ( ! top || ! *top )
        return 1;
    *val = (*top)->val;
    next = (*top)->next;
    free ( *top );
    *top = next;
    return 0;
}
 
#define BUF_LEN 32
 
int main(void){
    char buf[BUF_LEN];
    int val;
    node_t * stack;
    
    stack = NULL;
    printf("Enter some numbers. Empty string - finish.\n");
    while ( printf("> ") && fgets(buf, BUF_LEN, stdin) && *buf != '\n' ){
        if ( push(&stack, atoi(buf)) ){
            fprintf(stderr, "Memory error!\n");
            exit(EXIT_FAILURE);
        }
    }
    
    if ( ! stack ){
        fprintf(stderr, "Stack is empty!\n");
        exit(EXIT_FAILURE);
    }
    
    while ( stack ){
        if ( pop(&stack, &val) ){
            fprintf(stderr, "Stack error!\n");
            exit(EXIT_FAILURE);
        }
        printf("> %d\n", val);
    }
    
    exit(EXIT_SUCCESS);
}

int push(node_t ** top, int val){
    node_t * n;
    
    if ( ! top )
        return 1;
    if ( ( n = (node_t*)malloc(sizeof(node_t)) ) == NULL )
        return 1;
    n->val = val;
    n->next = *top;
    *top = n;
    return 0;
}

#include <stdio.h>
 
void reverse_numbers_print(void){
    int val;
    if ( scanf("%d", &val) != 1 )
        return;
    reverse_numbers_print();
    printf("%d\n", val);
}
 
int main(void){
    printf("Enter some numbers one by row. The single sign symbol - finish.\n");
    reverse_numbers_print();
    return 0;
}

#include <stdio.h>
 
void rec_reverse(const char * s){
    if ( ! *s )
        return;
    rec_reverse(s + 1);
    putchar(*s);
}
 
void it_reverse(const char * s){
    const char * p;
    for ( p = s; *p; ++p )
        ;
    while ( p > s )
        putchar(*--p);
}
 
int main(void){
    char buf[BUFSIZ];
 
    printf("String: ");
    scanf("%[^\n]%*c", buf);
    printf("Recursive: ");
    rec_reverse(buf);
    printf("\nIterative: ");
    it_reverse(buf);
    printf("\n");
 
    return 0;
}

#include <stdio.h>
 
char * rec_strchr(const char * s, char c){
    return ( *s == '\0' ) ? NULL : ( *s == c ) ? (char*)s : rec_strchr(++s, c);
}
 
int main(void){
    char * text = "This is a good day to die.";
    char c, * found;
 
    printf("String: %s\n", text);
    printf("Character to find in: ");
    scanf("%c", &c);
    if ( found = rec_strchr(text, c) )
        printf("Yes, it's a %d(th) from begin.\n", found - text + 1);
    else
        printf("Character '%c' not found.\n", c);
 
    return 0;
}

#include <stdio.h>
 
char * strreverse(char * s){
    char * pHead, * pTail, c;
 
    for ( pTail = s; *pTail; ++pTail )
        ;
    for ( --pTail, pHead = s; pHead < pTail; ++pHead, --pTail ){
        c = *pHead;
        *pHead = *pTail;
        *pTail = c;
    }
 
    return s;
}
 
int main(void){
    char buf[BUFSIZ];
 
    printf("String:  ");
    scanf("%[^\n]%*c", buf);
    printf("Reverse: %s\n", strreverse(buf));
 
    return 0;
}