C语言中缀式转后缀式代码

以下是C语言中缀式转后缀式的代码实现：

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

#define MAX_SIZE 100

int get_priority(char op) {
    switch (op) {
        case '+':
        case '-':
            return 1;
        case '*':
        case '/':
            return 2;
        case '(':
        case ')':
            return 0;
        default:
            return -1;
    }
}

void infix_to_postfix(char *infix, char *postfix) {
    int i, j, top = 0;
    char stack[MAX_SIZE], ch;
    
    for (i = 0, j = 0; infix[i] != '\0'; i++) {
        ch = infix[i];
        
        if (ch == '(') {
            stack[top++] = ch;
        } else if (ch == ')') {
            while (stack[top - 1] != '(') {
                postfix[j++] = stack[--top];
            }
            top--;
        } else if (ch >= '0' && ch <= '9') {
            postfix[j++] = ch;
        } else {
            while (top > 0 && get_priority(stack[top - 1]) >= get_priority(ch)) {
                postfix[j++] = stack[--top];
            }
            stack[top++] = ch;
        }
    }
    
    while (top > 0) {
        postfix[j++] = stack[--top];
    }
    postfix[j] = '\0';
}

int main() {
    char infix[MAX_SIZE], postfix[MAX_SIZE];
    
    printf("Enter an infix expression: ");
    gets(infix);
    
    infix_to_postfix(infix, postfix);
    
    printf("Postfix expression: %s\n", postfix);
    
    return 0;
}

该代码实现了一个简单的中缀式转后缀式的算法，可以将输入的中缀表达式转换为后缀表达式并输出。