uva11582Colossal Fibonacci Numbers!（快速幂+预处理）

这个题不预处理要超时的。。

代码：

#include <iostream>
#include <cstring>
#include <cstdio>
#include <vector>

using namespace std;
#define ll unsigned long long

const int maxn = 1e6;

ll a,b;
int n;

vector<int> f[1005];
int c[1005];

void init()

{
    for(int i = 2;i <= 1000;++i)
    {
        f[i].push_back(0);
        f[i].push_back(1);
        for(int j = 2; ;++j)
        {
            f[i].push_back((f[i][j - 1] + f[i][j - 2]) % i);
            if(f[i][j] == 1 && f[i][j - 1] == 0)
            {
                c[i] = j - 1;
                break;
            }
        }
    }
}
int pow_mod(ll y,int M)

{
    if(y == 0) return 1;
    int x = pow_mod(y / 2,M);
    ll ans = (ll) x * x % M;
    if(y % 2 == 1) ans = ((ans % M) * (a % M)) % M;
   // printf("ans = %llu\n",ans);
    return (int)ans;
}

int main()

{
    init();

    int t;
    cin >> t;
    while(t--)
    {
        //memset(f,0,sizeof(f));
        scanf("%llu%llu%d",&a,&b,&n);
        //printf("%llu %llu %d\n",a,b,n);
        if(!a || n == 1)
            printf("0\n");
        else if(!b)
            printf("1\n");
        else
        {
            //printf("M = %d\n",M);
            int x = pow_mod(b,c[n]);
            //printf("x = %llu\n",x);
            printf("%d\n",f[n][x]);
        }
    }
    return 0;
}