首页 > 代码库 > [BZOJ 1833] [ZJOI2010] count 数字计数 【数位DP】

[BZOJ 1833] [ZJOI2010] count 数字计数 【数位DP】

题目链接:BZOJ - 1833

 

题目分析

数位DP ..

用 f[i][j][k] 表示第 i 位是 j 的 i 位数共有多少个数码 k 。

然后差分询问...Get()中注意一下,如果固定了第 i 位,这一位是 t ,那么数码 t 的答案是要加一个值的(见代码)。

 

代码

#include <iostream>#include <cstdlib>#include <cstdio>#include <cstring>#include <cmath>#include <algorithm>using namespace std;const int MaxBit = 15;typedef long long LL;struct ES{	LL A[11];};ES operator + (const ES &a, const ES &b) {	ES ret;	for (int i = 0; i <= 9; ++i) ret.A[i] = a.A[i] + b.A[i];	return ret;}LL A, B;LL P10[MaxBit]; ES f[MaxBit][11];ES Get(LL x) {	ES ret;	for (int i = 0; i <= 9; ++i) ret.A[i] = 0;	if (x == 0) return ret;	int l = 1;	while (P10[l] <= x) ++l;	for (int i = 1; i <= l - 1; ++i) {		for (int j = 1; j <= 9; ++j) {			ret = ret + f[i][j];		}	}	//0没有被统计 	++ret.A[0];	LL t; 	t = x / P10[l - 1];	x %= P10[l - 1];	//如果只有1位,下面这里也会不统计0,但是已经在上面补上了0 	for (int i = 1; i <= t - 1; ++i) ret = ret + f[l][i];	ret.A[t] += x;	for (int i = l - 1; i >= 1; --i) {		t = x / P10[i - 1];		x %= P10[i - 1];		for (int j = 0; j <= t - 1; ++j) ret = ret + f[i][j];		ret.A[t] += x;	}	return ret;}int main() {	P10[0] = 1ll; 	for (int i = 1; i <= 13; ++i) P10[i] = P10[i - 1] * 10ll;	for (int i = 1; i <= 13; ++i) {		for (int j = 0; j <= 9; ++j) {			for (int k = 0; k <= 9; ++k) {				f[i][j] = f[i][j] + f[i - 1][k];			}			f[i][j].A[j] += P10[i - 1];		}	}	scanf("%lld%lld", &A, &B);	ES TA, TB;	TA = Get(A); TB = Get(B + 1);	for (int i = 0; i <= 9; ++i) {		printf("%lld", TB.A[i] - TA.A[i]);		if (i == 9) printf("\n");		else printf(" ");	}	return 0;}

  

[BZOJ 1833] [ZJOI2010] count 数字计数 【数位DP】