C言語で書いてみました

■ ヒープ（平成14年午後1問5）

#include <stdio.h>
#include <time.h>

/* 平成14年午後1問5 */

#define N   255

struct QUE {
    unsigned pri;
    long time;
    unsigned id;
} Q[N];

unsigned n = 0;

void put(unsigned priority, unsigned id)
{
    struct QUE t;
    unsigned r;
    n++;
    Q[n].pri = priority;
    Q[n].id  = id;
    Q[n].time = time(NULL);
    r = n;
    while (r != 1 && Q[r/2].pri > Q[r].pri) {
        t = Q[r];
        Q[r] = Q[r/2];
        Q[r/2] = t;
        r /= 2;
    }
}

unsigned get()
{
    struct QUE t;
    unsigned id, r;
    id = Q[1].id;
    Q[1] = Q[n];
    n--;
    r = 1;
    while (n >= 2*r) {
        if (Q[r].pri < Q[r*2].pri && Q[r].pri < Q[r*2+1].pri) break;
        if (n < 2*r+1 || Q[r*2].pri < Q[r*2+1].pri) {
            t = Q[r];
            Q[r] = Q[r*2];
            Q[r*2] = t;
            r *= 2;
        } else if (Q[r*2].pri > Q[r*2+1].pri) {
            t = Q[r];
            Q[r] = Q[r*2+1];
            Q[r*2+1] = t;
            r = r*2+1;
        }
    }
    return id;
}

void print_que()
{
    unsigned i;
    for (i = 1; i <= n; i++)
        printf("%2u ", Q[i].pri);
    putchar('\n');
}

int main()
{
    put(2, 1);
    put(5, 2);
    put(11, 3);
    put(8, 4);
    put(13, 5);
    put(15, 6);
    put(12, 7);
    put(9, 8);
    put(10, 9);
    printf("初期値   ：");
    print_que();

    get();
    printf("getのあと：");
    print_que();

    put(6, 10);
    printf("putのあと：");
    print_que();

    return 0;
}