【离散数学】编程练习：求命题公式的主范式

【离散数学】编程练习：求命题公式的主范式

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

#define N 50

char input[N];
bool table[N];
int cvt[N];
int value[N];

int order(char c)
{
    switch (c)
    {
    case '#':
        return -1;
    case '(':
        return 0;
    case '+':
        return 1;
    case '-':
        return 2;
    case '|':
        return 3;
    case '&':
        return 4;
    case '!':
        return 5;
    default:
        return 0;
    }
}

void postfix()
{

    char post[N] = {'\0'};

    int index = -1;

    char stack[N] = {'#'};

    int sub = 0;

    int len = strlen(input);

    for (int i = 0; i < len; i++)

    {

        if (input[i] >= 'a' && input[i] <= 'z')
        {
            post[++index] = input[i];
            continue;
        }
        if (input[i] == '!' || input[i] == '&' || input[i] == '|' || input[i] == '-' || input[i] == '+')
        {
            while (order(input[i]) <= order(stack[sub]))
                post[++index] = stack[sub--];
            stack[++sub] = input[i];
            continue;
        }
        if (input[i] == '(')
        {
            stack[++sub] = input[i];
            continue;
        }
        if (input[i] == ')')
        {
            while (stack[sub] != '(')
                post[++index] = stack[sub--];
            sub--;
            continue;
        }
    }

    while (sub)
        post[++index] = stack[sub--];

    strcpy(input, post);
}

int btoi()

{
    int sum = 0, weight = 1;
    for (int i = 25; i >= 0; i--)
        if (table[i])
        {
            if (cvt[i]) sum += weight;
            weight *= 2;
        }
    return sum;
}

int calc(int a, int b, char c)
{
    switch (c)
    {
        case '&': return a * b;
        case '|': if (a + b) return 1; else return 0;
        case '-': if (a == 1 && b == 0) return 0; else return 1;
        case '+': return !((a + b) & 1);
    }
}

int work()
{
    int stack[N], ps = -1;
    int len = strlen(input);
    for (int i = 0; i < len; i++)
    {
        if (input[i] >= 'a' && input[i] <= 'z')
        {
            stack[++ps] = cvt[input[i] - 'a'];
            continue;
        }
        if (input[i] == '!')
        {
            stack[ps] = (stack[ps] + 1) & 1;
            continue;
        }
        int ans = calc(stack[ps - 1], stack[ps], input[i]);
        stack[--ps] = ans;
    }
    return stack[0];
}

void assign()
{
    int x = btoi();
    int ans = work();
    value[x] = ans;}

void generate(char c)
{
    while (c <= 'z' && table[c - 'a'] == false)
        c++;
    if (c > 'z')
    {
        assign();
        return;
    }

    cvt[c - 'a'] = 0;

    generate(c + 1);

    cvt[c - 'a'] = 1;

    generate(c + 1);
}

int set_order()
{
    int v = 0;
    memset(table, 0, sizeof(table));

    int len = strlen(input);

    for (int i = 0; i < len; i++)

    {

        if (input[i] >= 'a' && input[i] < 'z')

            table[input[i] - 'a'] = true;
    }

    for (int i = 0; i < 26; i++)

        if (table[i])
            v++;

    v = pow(2, v);

    return v;
}

void outDis(int sum)
{
    int i = 0;
    while (i < sum && !value[i]) i++;
    if (i >= sum)
    {
        printf("0 ; ");
        return;
    }
    printf("m%d", i);
    for (i++; i < sum; i++)
        if (value[i]) printf(" ∨ m%d", i);
    printf(" ; ");
}

void outCon(int sum)
{
    int i = 0;
    while (i < sum && value[i]) i++;
    if (i >= sum)
    {
        printf("1\n");
        return;
    }
    printf("M%d", i);
    for (i++; i < sum; i++)
        if (!value[i]) printf(" ∧ M%d", i);
    printf("\n");
}

void result(int sum)
{
    generate('a');
    outDis(sum);
    outCon(sum);
}


int main()
{        int sum;
    scanf("%s", input);
    postfix();
    sum = set_order();
    result(sum);
    return 0;
}