A+B Problem（再升级）--完全背包

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luogu 1832

题目分析：

定义f[i]表示能表示出i号数字的方案数，易知f[i]+=f[i-s],s为素数
注意拓扑关系

Code：

#include <bits/stdc++.h>
using namespace std;
#define maxn 1010

int s[]={2,3,5,7,11,13,17,19,23,29,31,37,41,43,47,53,59,61,67,71,73,79,83,89,97,101,103,107,109,113,127,131,137,139,149,151,157,163,167,173,179,181,191,193,197,199,211,223,227,229,233,239,241,251,257,263,269,271,277,281,283,293,307,311,313,317,331,337,347,349,353,359,367,373,379,383,389,397,401,409,419,421,431,433,439,443,449,457,461,463,467,479,487,491,499,503,509,521,523,541,547,557,563,569,571,577,587,593,599,601,607,613,617,619,631,641,643,647,653,659,661,673,677,683,691,701,709,719,727,733,739,743,751,757,761,769,773,787,797,809,811,821,823,827,829,839,853,857,859,863,877,881,883,887,907,911,919,929,937,941,947,953,967,971,977,983,991,997,1009,1013,1019,1021,1031,1033,1039,1049,1051,1061,1063,1069};
int n;
long long f[maxn];

inline void init_() {
	freopen("a.txt","r",stdin);
}

inline int read_() {
	int x=0,f=1;
	char c=getchar();
	while(c<'0'||c>'9') {
		if(c=='-') f=-1;
		c=getchar();
	}
	while(c>='0'&&c<='9') {
		x=x*10+c-'0';
		c=getchar();
	}
	return x*f;
}

inline void readda_() {
	n=read_();
}

inline void work_() {
	memset(f,0,sizeof(f));
	f[0]=1;
	for(int i=0; ;i++) {
		if(s[i]>n) break;
		for(int j=s[i];j<=n;j++) {
			f[j]+=f[j-s[i]];
		}
	}
	printf("%lld",f[n]);
}

int main() {
	init_();
	readda_();
	work_();
	return 0;
}