'commit'

TangDou/Topic/P5091.cpp

@@ -0,0 +1,51 @@
+#include <bits/stdc++.h>
+using namespace std;
+#define int long long
+#define endl "\n"
+const int N = 2000010;
+
+// 求单个数字的欧拉函数
+int phi(int x) {
+    int res = x;
+    for (int i = 2; i <= x / i; i++)
+        if (x % i == 0) {
+            res = res / i * (i - 1);
+            while (x % i == 0) x /= i;
+        }
+    if (x > 1) res = res / x * (x - 1);
+    return res;
+}
+
+// 快速幂
+int qmi(int a, int b, int p) {
+    int res = 1;
+    a %= p;
+    while (b) {
+        if (b & 1) res = res * a % p;
+        b >>= 1;
+        a = a * a % p;
+    }
+    return res;
+}
+
+signed main() {
+    int a, c;
+    cin >> a >> c;
+    int p = phi(c);
+
+    // 将非数字字符，比如空格读没
+    char ch;
+    ch = getchar();
+    while (ch < '0' || ch > '9') ch = getchar();
+
+    // 当是数字字符时，一直读入
+    int b = 0;
+    while (ch >= '0' && ch <= '9') {
+        b = b * 10 + ch - '0';
+        if (b >= p) // 检查b是否大于等于phi(c)
+            b = b % p + p;
+        // 继续读入下一个字符
+        ch = getchar();
+    }
+    printf("%lld\n", qmi(a, b, c)); // 按快速幂来计算就行了
+}