POJ2506 (Tiling)

#include <stdio.h>
#include <string.h>
int a[310][310];
int main()
{
    int n, i, j, s, k, p;
    while (scanf("%d", &n) != EOF)
    {
        memset(a, 0, sizeof(a));
        a[0][0] = 1;//初始化
        a[1][0] = 1;
        a[2][0] = 3;
        if (n <= 2)
        {
            printf("%d\n", a[n][0]);
        }
        else
        {
            s = 1;
            for (i = 3; i <= n; ++i)
            {
                k = 0; //记录是否超过十
                p = 0;
                for (j = 0; j < s; ++j)
                {
                    p = a[i - 2][j] * 2 + a[i - 1][j] + k;
                    a[i][j] = p % 10;
                    k = p / 10;
                }
                if (k)//位数增加一位时的处理
                {
                    a[i][s] = k;
                    s ++;
                }
            }
            for (i = s - 1; i >= 0; --i)
            {
                printf("%d", a[n][i]);
            }
            printf("\n");
        }
    }
    return 0;
}