40 lines
810 B
C++
40 lines
810 B
C++
#include <cstdio>
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#include <cstring>
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#include <iostream>
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#include <algorithm>
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#define LL long long
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using namespace std;
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LL n, p;
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LL multi(LL a, LL b) {
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LL ret = 0;
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while(b) {
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if(b & 1) ret = (ret + a) % p;
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a = (a + a) % p;
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b >>= 1;
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}
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return ret;
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}
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LL powmod(LL a, LL b) {
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LL ret = 1;
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while(b) {
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if(b & 1) ret = multi(ret, a) % p;
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a = multi(a, a) % p;
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b >>= 1;
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}
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return ret;
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}
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int main() {
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while(cin >> n >> p) {
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if(p == 1) {
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cout << 0 << endl;
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} else if(n == 1) {
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cout << 1 << endl;
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} else {
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LL ans = powmod(2, n) - 2;
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if(ans < 0) ans += p;
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cout << ans << endl;
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}
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}
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return 0;
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}
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