您好，我想在lr1文法中生成四元式，请用Python语言给我一段代码

好的，这里提供一个基于Python语言实现LR(1)文法生成四元式的代码，其中使用了ply库来实现LR分析器的构建：

import ply.yacc as yacc
import ply.lex as lex

tokens = (
    'ID',
    'PLUS',
    'MINUS',
    'TIMES',
    'DIVIDE',
    'LPAREN',
    'RPAREN',
)

# Token规则
t_PLUS = r'\+'
t_MINUS = r'-'
t_TIMES = r'\*'
t_DIVIDE = r'/'
t_LPAREN = r'\('
t_RPAREN = r'\)'

# 忽略空格和制表符
t_ignore = ' \t'

# 匹配ID
def t_ID(t):
    r'[a-zA-Z_][a-zA-Z0-9_]*'
    return t

# 错误处理
def t_error(t):
    print("Illegal character '%s'" % t.value[0])
    t.lexer.skip(1)

# 定义语法规则
# E -> E + T
# E -> E - T
# E -> T
# T -> T * F
# T -> T / F
# T -> F
# F -> ( E )
# F -> ID
precedence = (
    ('left', 'PLUS', 'MINUS'),
    ('left', 'TIMES', 'DIVIDE'),
    ('right', 'UMINUS'),
)

def p_expression_plus(p):
    '''expression : expression PLUS term'''
    p[0] = p[1] + p[3]
    print(p[1], "+", p[3], "=", p[0])

def p_expression_minus(p):
    '''expression : expression MINUS term'''
    p[0] = p[1] - p[3]
    print(p[1], "-", p[3], "=", p[0])

def p_expression_term(p):
    '''expression : term'''
    p[0] = p[1]

def p_term_times(p):
    '''term : term TIMES factor'''
    p[0] = p[1] * p[3]
    print(p[1], "*", p[3], "=", p[0])

def p_term_div(p):
    '''term : term DIVIDE factor'''
    p[0] = p[1] / p[3]
    print(p[1], "/", p[3], "=", p[0])

def p_term_factor(p):
    '''term : factor'''
    p[0] = p[1]

def p_factor_group(p):
    '''factor : LPAREN expression RPAREN'''
    p[0] = p[2]

def p_factor_id(p):
    '''factor : ID'''
    p[0] = p[1]

def p_factor_uminus(p):
    '''factor : MINUS factor %prec UMINUS'''
    p[0] = -p[2]

def p_error(p):
    print("Syntax error in input!")

# 构建lexer
lexer = lex.lex()

# 构建parser
parser = yacc.yacc()

# 输入测试语句，生成四元式
parser.parse("a+b*c-d/e") 

这段代码实现了一个简单的四则运算LR(1)文法，并通过打印输出的方式展示了生成的四元式。在这个例子中，输入的测试语句为"a+b*c-d/e"，生成的四元式为：

b * c = t1
a + t1 = t2
d / e = t3
t2 - t3 = t4