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39 lines
759 B
C++
39 lines
759 B
C++
#include <iostream>
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#include <fstream>
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// using std::cin;
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// using std::cout;
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std::ifstream cin("string.in");
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std::ofstream cout("string.out");
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const char endl = '\n';
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const int N = 1e6 + 5;
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const int mod = 998244353;
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int a, b, inv[N << 2], ans;
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int main() {
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std::ios::sync_with_stdio(false);
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cin.tie(nullptr);
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cin >> a >> b;
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inv[0] = inv[1] = 1;
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for (int i = 2; i <= a + a + b; i++) {
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inv[i] = static_cast<long long>(mod - mod / i) * inv[mod % i] % mod;
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}
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for (int i = 1; i <= a; i++) {
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ans = (static_cast<long long>(ans) + inv[2 * i - 1]) % mod;
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}
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for (int i = 1; i <= b; i++) {
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ans = (static_cast<long long>(ans) + inv[2 * a + i]) % mod;
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}
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cout << ans << endl;
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return 0;
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}
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