41 lines
882 B
C++
41 lines
882 B
C++
#include <bits/stdc++.h>
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using namespace std;
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#define int long long
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const int MOD = 200907;
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// 龟速乘,快速加
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int qadd(int a, int b) {
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int res = 0;
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while (b) {
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if (b & 1) res = (res + a) % MOD;
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b >>= 1;
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a = (a + a) % MOD;
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}
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return res;
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}
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// 快速幂
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int qmi(int a, int b) {
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int res = 1;
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while (b) {
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if (b & 1) res = (res * a) % MOD;
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b >>= 1;
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a = a * a % MOD;
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}
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return res;
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}
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signed main() {
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int T;
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cin >> T;
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while (T--) {
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int a, b, c, k;
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cin >> a >> b >> c >> k;
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if (a + c == b + b)
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cout << (qadd(b - a, k - 1) + a) % MOD << endl; // 为等差即套公式,首项+公差*(项数-1)
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else
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cout << qmi(b / a, k - 1) * a % MOD << endl; // 等比数列用快速幂算末项
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}
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}
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