bzoj1263

贪心

n%3==1 分出一个4，其余用3，n%3==2，分出一个2，其余用3，然后高精度就行了

#include<bits/stdc++.h>
using namespace std;
const int N = 5005;
struct BigInt {int len;int a[N];BigInt() { memset(a, 0, sizeof(a)); }BigInt friend operator * (const BigInt &a, const int &x) {BigInt ret;ret.len = a.len;for(int i = 1; i <= ret.len; ++i) ret.a[i] = a.a[i] * x;for(int i = 1; i <= ret.len; ++i) ret.a[i + 1] += ret.a[i] / 10, ret.a[i] %= 10;while(ret.a[ret.len + 1]) {++ret.len;ret.a[ret.len + 1] += ret.a[ret.len] / 10;ret.a[ret.len] %= 10;} return ret;}void print(){printf("%d\n", len);for(int i = len; i > max(len - 100, 0); --i) printf("%d", a[i]);puts("");}
} A;
int n;
int main()
{scanf("%d", &n);A.a[1] = A.len = 1; if(n % 3 == 1) n -= 4, A = A * 4;if(n % 3 == 2) n -= 2, A = A * 2;for(int i = 1; i <= n / 3; ++i) A = A * 3;A.print(); return 0;
}