麻雀さんに殺されました

majan.c

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

#define MODE_ATAMA 0
#define MODE_SHUNTSU 1

#define NEW_PATTERN(i, copy_n, ns, ns_size, pats, pats_i, pats_size)    \
    do {    \
        int j;    \
        pat_t pat;    \
        if(ns_size == 13) {    \
            pats_size++;    \
            pats[pats_i][0].i = 0;    \
        }    \
        for(j = 0; j < copy_n; j++) {    \
            pat.nums[j] = ns[i + j];    \
        }    \
        pats[pats_i][++(pats[pats_i][0].i)] = pat;    \
        pattern(ns, ns_size, i, i, i+1, mode, pats, pats_i, &pats_size);     \
        pats_i = pats_size;    \
    }while(0)    \


typedef struct {
    int nums[3];
    int i;
} pat_t;

int pattern(int *old_ns, int old_ns_size, int exception1, int exception2, int exception3, int mode, pat_t pats[][6], int pats_i, int *pats_size)
{
    int ns[13];
    int ns_size = old_ns_size;
    int i = 0;
    for(i = 0; i < ns_size; i++) {
        if(i != exception1 && i != exception2 && i != exception3) {
            ns[j] = old_ns[j];
            j++;
        } else {
            ns_size--;
        }
    }
    if(ns_size < 3) {
        if(ns[i] == ns[i+1] && ns[i] != ns[i+2] && mode != MODE_ATAMA) {    // ATAMA
            NEW_PATTERN(i, 2, ns, ns_size, pats, pats_i, pats_size);
            return pats_size;
        } else {
            pats[pats_i][0].i = -1;
            return pats_size;
        }
    }
    for(i = 0; i < old_ns_size - 2; i++) {
        if(ns[i] == ns[i+1] && ns[i] == ns[i+2]) {    // KOTSU
            NEW_PATTERN(i, 3, ns, ns_size, pats, pats_i, pats_size);
        }
        if(ns[i] == ns[i+1] && ns[i] != ns[i+2] && mode != MODE_ATAMA) {    // ATAMA
            NEW_PATTERN(i, 3, ns, ns_size, pats, pats_i, pats_size);
        }
        if(ns[i] == ns[i+1]+1 && ns[i] == ns[i+2]+2) {    // SHUNTSU
            NEW_PATTERN(i, 3, ns, ns_size, pats, pats_i, pats_size);
        }
        if(!(ns[i] == ns[i+1] && ns[i] == ns[i+2]) ||
                !(ns[i] == ns[i+1] && ns[i] != ns[i+2] && mode != MODE_ATAMA) ||
                !(ns[i] == ns[i+1]+1 && ns[i] == ns[i+2]+2)) {
            pats[pats_i][0].i = -1;
        }
        return pats_size;
    }
}

int main()
{
    int ns[13];
    pat_t pats[1000][6];
    int pats_size = 0;
    int i = 0;
    for(i = 0; i < 13; i++) {
        ns[i] = getchar();
    }
    for(i = 0; i < 13; i++) {
        if(ns[i] + 1 == ns[i+1] || ns[i] == ns[i+1]) {
            int mode;
            if(ns[i] == ns[i+1]) {
                mode = MODE_ATAMA;
            } else {
                mode = MODE_SHUNTSU;
            }
            pattern(ns, 13, i, i, i+1, mode, pats, pats_size, &pats_size);
        }
    }
}