'commit'

TangDou/AcWing/Qmi/876.cpp

@@ -0,0 +1,28 @@
+#include <bits/stdc++.h>
+
+using namespace std;
+#define int long long
+
+// 快速幂 (a^k)%p
+int qmi(int a, int k, int p) {
+    int res = 1;
+    while (k) {
+        if (k & 1) res = res * a % p;
+        a = a * a % p;
+        k >>= 1;
+    }
+    return res;
+}
+
+signed main() {
+    int n;
+    cin >> n;
+    while (n--) {
+        int a, p;
+        cin >> a >> p;
+        if (a % p == 0)
+            puts("impossible"); // 不互质
+        else
+            printf("%lld\n", qmi(a, p - 2, p));
+    }
+}