一段长度为n的序列,你有红黄蓝绿四种颜色的砖块,一块砖长度为1,问你铺砖的方案数,其中红黄颜色之和必须为偶数。
#include <queue> #include <stack> #include <cmath> #include <cstdio> #include <string> #include <vector> #include <cstring> #include <iostream> #include <algorithm> using namespace std; #define fi first #define se second typedef long long LL; typedef unsigned long long ULL; typedef pair<int, int> pii; typedef pair<LL, LL> pll; const int maxn = 1000 + 5; const int maxm = 100 + 5; const int inf = 0x3f3f3f3f; const LL mod = 10000 + 7;//19260817 const double pi = acos(-1.0); LL n, res; LL fpow(LL a, LL n){ LL ans = 1; while(n){ if(n & 1) ans = ans * a % mod; a = a * a % mod; n >>= 1; } return ans; } int main(){ int T; scanf("%d", &T); while(T--){ scanf("%lld", &n); printf("%lld ", (1LL * fpow(4, n - 1) % mod + fpow(2, n - 1) % mod) % mod); } return 0; } 原文链接:https://blog.csdn.net/qq_43464645/article/details/95488472