对文法G[S]：S→a|∧|(T)；T→T，S|S。对文法进行改写，对每个非终结符写出不带回溯的递归子程序

改写后的文法如下：

S → aS' | ∧
S' → TS' | S'
T → T,S | S

对应的不带回溯的递归子程序如下：

void S() {
    if (lookahead == 'a') {
        match('a');
        S'();
    } else if (lookahead == EPSILON) {
        // do nothing
    } else {
        error();
    }
}

void S'() {
    if (lookahead == 'a') {
        match('a');
        S'();
    } else if (lookahead == '(' || lookahead == 'a') {
        T();
        S'();
    } else if (lookahead == ')' || lookahead == '$') {
        // do nothing
    } else {
        error();
    }
}

void T() {
    if (lookahead == '(' || lookahead == 'a') {
        S();
        T_();
    } else {
        error();
    }
}

void T_() {
    if (lookahead == ',') {
        match(',');
        S();
        T_();
    } else if (lookahead == ')' || lookahead == '$') {
        // do nothing
    } else {
        error();
    }
}