用c语言生成一段中缀表达式转后缀表达式的完整代码

在C语言中，将中缀表达式转换成后缀表达式（也称为逆波兰表示法，RPN），通常会涉及到栈数据结构的使用。这里是一个简单的示例，展示如何实现这个功能：

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

#define MAX_TOKEN_SIZE 50
#define PRECEDENCE(op) ((op)=='^'?3:(op)=='*'?2:(op)=='/'?1:0)

typedef enum { NUMBER, LEFT_PAREN, RIGHT_PAREN, OPERAND } TokenType;

struct Stack {
    char* items;
    int top;
};

void push(struct Stack* stack, char item);
char pop(struct Stack* stack);
char peek(struct Stack* stack);

bool isOperator(char op);
int getPrecedence(char op);

void infixToRPN(char* infix, char* rpn) {
    int i = 0, j = 0;
    struct Stack stack;
    stack.items = (char*)malloc(sizeof(char)*MAX_TOKEN_SIZE);
    stack.top = -1;

    while (infix[i] != '\0') {
        if (isdigit(infix[i])) {
            // Add numbers to the RPN output
            rpn[j++] = infix[i];
            while (isdigit(infix[++i])) rpn[j++] = infix[i];
        } else if (infix[i] == '(') {
            push(&stack, '(');
        } else if (infix[i] == ')') {
            while (peek(&stack) != '(') {
                rpn[j++] = pop(&stack);
            }
            pop(&stack); // Discard the left parenthesis
        } else {
            while (stack.top != -1 && getPrecedence(stack.peek()) >= getPrecedence(infix[i])) {
                rpn[j++] = pop(&stack);
            }
            push(&stack, infix[i]);
        }
    }

    // Add remaining operators
    while (stack.top != -1) {
        rpn[j++] = pop(&stack);
    }

    rpn[j] = '\0'; // Null terminate the RPN string
    printf("Infix: %s\n", infix);
    printf("RPN: %s\n", rpn);
}

void push(struct Stack* stack, char item) {
    stack->items[++stack->top] = item;
}

char pop(struct Stack* stack) {
    return stack->items[stack->top--];
}

char peek(struct Stack* stack) {
    return stack->items[stack->top];
}

bool isOperator(char op) {
    return op == '+' || op == '-' || op == '*' || op == '/';
}

int getPrecedence(char op) {
    return PRECEDENCE(op);
}

int main() {
    char infix[] = "A + B * C";
    char rpn[MAX_TOKEN_SIZE];

    infixToRPN(infix, rpn);
    return 0;
}