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#include <cstdio>
#include <complex>
#include <cstring>
#include <cmath>
using namespace std;
typedef complex<double> Comp;
const Comp (0, 1);
const int MAX_N = 50000 + 10;
#ifndef M_PI
#define M_PI 3.14159265358979323846
#endif
Comp tmp[1 << 17];
void DFT(Comp a, int n, int rev) {
if (n == 1) return;
for (int i = 0; i < n; i++) {
tmp[i] = a[i];
}
for (int i = 0; i < n; i++) {
if (i & 1)
a[n / 2 + i / 2] = tmp[i];
else
a[i / 2] = tmp[i];
}
Comp a0 = a, a1 = a + n / 2;
DFT(a0, n / 2, rev);
DFT(a1, n / 2, rev);
Comp cur(1, 0);
double alpha = 2 M_PI / n rev;
Comp step = exp(I alpha);
for (int k = 0; k < n / 2; k++) {
tmp[k] = a0[k] + cur a1[k];
tmp[k + n / 2] = a0[k] - cur a1[k];
cur = step;
}
for (int i = 0; i < n; i++) {
a[i] = tmp[i];
}
}
char A[MAX_N], B[MAX_N];
Comp a[1 << 17] = { }, b[1 << 17] = { };
int res[1 << 17];
int main() {
while (scanf("%s %s", A, B) != EOF) {
int lA = strlen(A), lB = strlen(B);
int n = 1;
while (n < lA + lB) n <<= 1;
for (int i = 0; i < n; i++) {
a[i] = 0;
b[i] = 0;
}
for (int i = 0; i < lA; i++) {
a[i] = A[lA - 1 - i] - '0';
}
for (int i = 0; i < lB; i++) {
b[i] = B[lB - 1 - i] - '0';
}
DFT(a, n, 1);
DFT(b, n, 1);
for (int i = 0; i < n; i++) {
a[i] *= b[i];
}
DFT(a, n, -1);
for (int i = 0; i < n; i++) {
a[i] /= n;
}
memset(res, 0, sizeof(res));
for (int i = 0; i + 1 < n; i++) {
res[i] += int(a[i].real() + 0.5);
res[i + 1] = res[i] / 10;
res[i] %= 10;
}
int k = n - 1;
while (res[k] == 0) k--;
if (k < 0) {
printf("0");
} else {
while (k >= 0) printf("%d", res[k--]);
}
printf("n");
}
return 0;
}
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