挑战数据结构和算法——栈的push、pop序列

#define push 1
#define pop -1

bool judge_push_pop(int *a, int *b, int len_a, int len_b){
    if (NULL == a || NULL == b || len_a != len_b) return false;
    int *p_a = a;
    int *p_b = b;
    int *op = (int *)malloc(sizeof(int) * len_a * 2);
    int index = 0;
    int i = 0;
    while(i < len_a){
        op[index] = push;

        index ++;

        if (*p_a == *p_b){
            p_b ++;
            op[index] = pop;
            index ++;
        }

        p_a ++;
        i ++;
    }
    while(index < len_a * 2){
        op[index++] = pop;
    }

    // judge
    int start = 0;
    int end = len_a * 2 - 1;
    while(start < end){
        if (op[start] + op[end] == 0){
            start ++;
            end --;
        }else return false;
    }

    return true;
    free(op);
}