最小邮票数【清华大学】

01背包

#include <cstdio>
#include <iostream>
#include <cstring>
#include <vector>
using namespace std;
const int N = 32;
const int M = 128;
const int MAX = 0x3f3f3f3f;
int w[N];                     
int main(){
    
    
	int m, n;
	scanf("%d %d", &m, &n);
	memset(w, 0, sizeof w);
	vector<vector<int>>f(n+1, vector<int>(m+1, MAX));
	for(int i = 1; i <= n; i++){
    
    
		scanf("%d", &w[i]);
	}
	for(int i = 0; i <= n; i++) f[i][0] = 0;
	for(int i = 1; i <= n; i++){
    
    
		for(int j = 0; j <= m; j++){
    
    
			if(j >= w[i] ) f[i][j] = min(f[i-1][j],f[i-1][j-w[i]]+1);
			else f[i][j] = f[i-1][j]; 
		}
	}
	if(f[n][m]==MAX){
    
    
		cout<<0<<endl;
	} else{
    
    
		cout<<f[n][m]<<endl;
	}
	return 0;
}