测试了Miller_Rabin和pollard_rho
题目里这个g(n)是有结论的，但我搞不太懂
最后f(n)/g(n) = (p1 + 1)(p2 + 1)...(pk + 1)
1 #include <cstdio> 2 #include <time.h> 3 #include <algorithm> 4 #include <cstring> 5 #define MOD 1000000007 6 using namespace std; 7 typedef long long LL; 8 9 const int S = 8; 10 11 LL mul(LL a, LL b, LL c) { 12 a %= c; 13 b %= c; 14 LL res = 0; 15 while (b) { 16 if (b & 1) { 17 res += a; 18 if (res > c) res -= c; 19 } 20 a <<= 1; 21 if (a > c) a -= c; 22 b >>= 1; 23 } 24 return res; 25 } 26 27 LL QP(LL x, LL n, LL p) { 28 LL res = 1; 29 x %= p; 30 while (n) { 31 if (n & 1) res = mul(res, x, p); 32 x = mul(x, x, p); 33 n >>= 1; 34 } 35 return res; 36 } 37 38 bool ck(LL a, LL n, LL x, LL t) { 39 LL res = QP(a, x, n); 40 LL last = res; 41 for (int i = 1; i <= t; i++) { 42 res = mul(res, res, n); 43 if (res == 1 && last != 1 && last != n - 1) return true; 44 last = res; 45 } 46 if (res != 1) return true; 47 else return false; 48 } 49 50 bool Miller_Rabin(LL n) { 51 if (n < 2) return false; 52 if (n == 2) return true; 53 if ( (n & 1) == 0) return false; 54 LL x = n - 1; 55 LL t = 0; 56 while ((x & 1) == 0) {x >>= 1; t++;} 57 srand(time(NULL)); 58 for (int i = 0; i < S; i++) { 59 LL a = rand() % (n - 1) + 1; 60 if (ck(a, n, x, t)) return false; 61 } 62 return true; 63 } 64 65 LL fact[100]; 66 int tol; 67 68 LL gcd(LL a, LL b) { 69 LL t; 70 while (b) { 71 t = a; 72 a = b; 73 b = t % b; 74 } 75 if (a >= 0) return a; 76 else return -a; 77 } 78 79 80 LL pollard_rho(LL x, LL c) { 81 LL i = 1, k = 2; 82 srand(time(NULL)); 83 LL x0 = rand() % (x - 1) + 1; 84 LL y = x0; 85 while (1) { 86 i++; 87 x0 = (mul(x0, x0, x) + c) % x; 88 LL d = gcd(y - x0, x); 89 if (d != 1 && d != x) return d; 90 if (y == x0) return x; 91 if (i == k) {y = x0; k += k;} 92 } 93 } 94 95 void findfac(LL n, int k) { 96 if (n == 1) return; 97 if (Miller_Rabin(n)) { 98 fact[tol++] = n; 99 return; 100 } 101 LL p = n; 102 int c = k; 103 while (p >= n) p = pollard_rho(p, c--); 104 findfac(p, k); 105 findfac(n / p, k); 106 } 107 108 int main() { 109 110 int T; 111 LL n; 112 scanf("%d", &T); 113 while (T--) { 114 scanf("%lld", &n); 115 if (Miller_Rabin(n)) { 116 tol = 1; fact[0] = n; 117 } else { 118 tol = 0; 119 findfac(n, 107); 120 } 121 sort(fact, fact + tol); 122 tol = unique(fact, fact + tol) - fact; 123 LL ans = 1; 124 for (int i = 0; i < tol; i++) { 125 ans = ans * (fact[i] + 1) % MOD; 126 } 127 printf("%lld ", ans); 128 } 129 130 131 return 0; 132 }