10828번 스택

C언어 코드이다. 

기본적인 스택 구현이다. 

https://www.acmicpc.net/problem/10828

#include <stdio.h>
#include <stdlib.h>
#include <malloc.h>
#include <string.h>
 
typedef struct Stack
{
    int data;
    struct Stack *next;
}Stack;
 
Stack * top = NULL;
 
void Push(int data)
{
    Stack * temp = (Stack*)malloc(sizeof(Stack));
 
    temp->data = data;
    temp->next = NULL;
 
    if (top == NULL)
    {
        // 최초 Push
 
        top = temp;
 
        return;
    }
 
    temp->next = top;
    top = temp;
 
    return;
}
 
int Pop()
{
    if (top == NULL) return -1;
    
    int ret = top->data;
 
    top = top->next;
 
    return ret;
}
 
int Size()
{
    if (top == NULL) return 0;
 
    Stack * temp = NULL;
 
    temp = top;
 
    int ret = 0;
 
    while (temp)
    {
        temp = temp->next;
 
        ++ret;
    }
 
    return ret;
}
 
int Empty()
{
    if (top == NULL) return 1;
    else return 0;
}
 
int Top()
{
    if (top == NULL) return -1;
 
    int ret = top->data;
 
    return ret;
}
 
int main(void)
{
    char input[10];
    int input_number = 0, N = 0;
 
    scanf("%d", &N);
 
    while (N--)
    {
        scanf("%s", input);
 
        if (strcmp(input, "push") == 0)
        {
            scanf("%d", &input_number);
 
            Push(input_number);
        }
        else if (strcmp(input, "pop") == 0)
        {
            printf("%d\n", Pop());
        }
        else if (strcmp(input, "size") == 0)
        {
            printf("%d\n", Size());
        }
        else if (strcmp(input, "empty") == 0)
        {
            printf("%d\n", Empty());
        }
        else if (strcmp(input, "top") == 0)
        {
            printf("%d\n", Top());
        }
    }
 
    return 0;
}