10106.cpp

#include <cmath>
#include <cstdio>
#include <cstring>

using namespace std;

int main(void)
{
    char num[300];
    int  i, j, lenA, lenB;
    long A[40], B[40], C[80];

    while (scanf("%s", num) != EOF) {
        for (i = 0; i < 40; ++i) {
            A[i] = 0;
            B[i] = 0;
        }
        lenA = strlen(num);
        for (j = 1; j <= lenA; ++j)
            A[(lenA - j) / 8] += (long)(num[j - 1] - '0') * pow(10, (lenA - j) % 8);
        lenA = lenA / 8;

        scanf("%s", num);
        lenB = strlen(num);
        for (j = 1; j <= lenB; ++j)
            B[(lenB - j) / 8] += (long)(num[j - 1] - '0') * pow(10, (lenB - j) % 8);
        lenB = lenB / 8;

        for (i = 0; i < 80; ++i)
            C[i] = 0;
        for (i = 0; i <= lenA; ++i)
            for (j = 0; j <= lenB; ++j) {
                C[i + j] += A[i] * B[j];
                if (C[i + j] >= 100000000) {
                    C[i + j + 1] += C[i + j] / 100000000;
                    C[i + j] %= 100000000;
                }
            }
        i = 79;
        while (C[i] < 1 && i > 0)
            i--;
        printf("%ld", C[i]);
        while (i > 0)
            printf("%08ld", C[--i]);
        printf("\n");
    }

    return 0;
}