01 knapsack problem

Description] [Title
a traveler can hold a maximum of M kg backpack, there are n items, their weight are W1, W2, ..., Wn, their value are C1, C2, ... , Cn, travelers can seek to maximize the total value.

[Input]
The first line: two integers, M (backpack capacity, M≤200) and N (number of items, N≤30);

First 2..N + 1 line: two integers each line Wi, Ci, and represents the weight value of each item.

[Output]
is only one line, a number that indicates the maximum total value.

[Input] Sample
10. 4
2. 1
. 3. 3
. 4. 5
. 7. 9

[Output] Sample
12

Dynamic programming method

#include<iostream>
#include<cstdio>
#include<cstdlib>
#include<cstring>
#define N 1001
using namespace std;

int m,n;
int w[N],c[N],f[N];

void fun(int cost,int weight)
{
    for(int v=m;v>=weight;v--)
        f[v]=max(f[v],f[v-weight]+cost);
}


int main(){
	cin>>m>>n;
	for(int i=1; i<=n; ++i)
		cin>>w[i]>>c[i];
	for(int i=1; i<=n; ++i){
		fun(c[i],w[i]);
	}
	cout<<f[m]<<endl;
    return 0;
}