Form1_DP/Knapsack.cpp at main · rahulpaul-07/Form1_DP · GitHub

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

int n;
int w[3003];
int v[3003];
int W;

int dp[3003][3003];

int rec(int i, int x){

    // pruning
    // (not needed here)

    // basecase
    if(i == n){
        return 0;
    }

    // cache check
    if(dp[i][x] != -1){
        return dp[i][x];
    }

    // transition
    int ans = rec(i+1, x);

    if(w[i] <= x){
        ans = max(ans, rec(i+1, x - w[i]) + v[i]);
    }

    // save and return
    dp[i][x] = ans;
    return ans;
}

void solve(){

    cin >> n;

    for(int i = 0; i < n; i++){
        cin >> w[i];
    }

    for(int i = 0; i < n; i++){
        cin >> v[i];
    }

    cin >> W;

    memset(dp, -1, sizeof(dp));

    cout << rec(0, W) << endl;
}

int main(){

    solve();

}