【扬中集训DAY2T2】 机智的AmyZhi

【题目链接】

           点击打开链接

【算法】

         据说标算是暴力？ 从N-200开始搜 

         不过我用了搜索+一些奇怪的剪枝，也A了....

【代码】

         标程

         

#include<bits/stdc++.h>
#define ll long long
using namespace std;
ll n,cases;
bool check(ll x){
	ll tmp=x;
	for(int i=1;i<=20;i++){
		tmp+=x%10;
		x/=10;
	}
	if(tmp==n)return 1;
	return 0;
}
int main(){
		scanf("%I64d",&cases);
		int flag;
		while(cases--)
		{
			flag=0;
			scanf("%I64d",&n);
			for(ll i=max(1LL,n-200);i<=n;i++)
				if(check(i)){
					printf("%I64d\n",i);
					flag=1;
					break;
				}
			if (flag==0) puts("Stupid SiriusRen");
		}
	return 0;
}

我的程序

#include<bits/stdc++.h>
using namespace std;
#define MAXL 17
typedef long long LL;

LL i,j,l,T,N,len,lth,sum;
LL a[MAXL+10][MAXL+10],s[MAXL+10][MAXL+10],f[MAXL+10],ans[MAXL+10];
vector<LL> vec,res;
bool solved;

template <typename T> inline void read(T &x) {
	int f = 1; x = 0;
	char c = getchar();
	for (; !isdigit(c); c = getchar()) { if (c == '-') f = -f; }
	for (; isdigit(c); c = getchar()) x = (x << 3) + (x << 1) + c - '0';
}

template <typename T> inline void write(T x) {
	if (x < 0) { putchar('-'); x = -x; }
	if (x > 9) write(x/10);
	putchar(x%10+'0');
}

template <typename T> inline void writeln(T x) {
	write(x);
	puts("");
}

inline void save_answer() {
	int i;
	for (i = 1; i <= len; i++) res.push_back(ans[i]);	
} 

inline void dfs(int dep) {
	int i,l,r;
	if (solved) return;
	if (sum > N) return;
	if (sum + 9 * (s[len][len] - s[len][dep-1]) < N) return;
	if (dep > len) {
		if (sum == N) {
			solved = true;
			save_answer();
		}
	} else {
		l = 0; r = 9;
		if (dep == 1) l = 1;
		for (i = l; i <= r; i++) {
			if (solved) break;
			if (sum + a[len][dep] * i <= N) {
				sum += a[len][dep] * i;
				ans[++lth] = i;
				dfs(dep+1);
				sum -= a[len][dep] * i;
				--lth;
			}
		}
	}	
}

void print() {
	int i;
	for (i = 0; i < res.size(); i++) write(res[i]);
	cout<<endl;
}

int main() {
	
	freopen("amy.in","r",stdin);
	freopen("amy.out","w",stdout);
	
	f[0] = 1;
	for (i = 1; i <= MAXL; i++) f[i] = (f[i-1] << 3) + (f[i-1] << 1); 
	for (i = 1; i <= MAXL; i++) {
		a[i][i] = 2;
		for (j = i - 1; j >= 1; j--) {
			a[i][j] = f[i-j] + 1; 
		}	
	} 
	for (i = 1; i <= MAXL; i++) {
		for (j = 1; j <= MAXL; j++) {
			s[i][j] = s[i][j-1] + a[i][j];
		}
	}
	read(T);
	while (T--) {
		vec.clear(); res.clear();
		solved = false;
		read(N);
		for (l = 1; l <= MAXL; l++)	{
			if (s[l][l] * 9 < N) continue;
			if (a[l][1] > N) break;
			vec.push_back(l);
		}
		for (i = 0; i < vec.size(); i++) {
			lth = sum = 0; len = vec[i];
			dfs(1);
			if (solved) break;
		}
		if (solved) print();
		else puts("Stupid SiriusRen");
	}
	
	return 0;

}