### Jedidiah's blog

By Jedidiah, history, 12 months ago, I don't understand why my code is giving TLE. Not able to catch the bug. Any help would be appreciated !!! Link to Question

#include<bits/stdc++.h>
# define    all(a)              a.begin(), a.end()
#define MOD (long long int )1e9+7
using namespace std;

typedef long long int ll;

ll dp;
ll solve(int index, ll currweight, ll weight, vector<vector<int>> nums, int n) {
if (index == n)
return 0;
if (dp[index][currweight] != -1)
return dp[index][currweight];
ll res = solve(index+1, currweight, weight, nums, n);
if (currweight+nums[index] <= weight) {
res = max(res, nums[index] + solve(index+1, currweight+nums[index], weight, nums, n));
}
dp[index][currweight] = res;
return res;
}

int main() {
#ifndef ONLINE_JUDGE
// for getting input from input.txt
freopen("input.txt", "r", stdin);
// for writing output to output.txt
freopen("output.txt", "w", stdout);
#endif
int n, k;
cin >> n >> k;
vector<vector<int>> nums(n, vector<int>(2));
for (int i=0; i<n; i++) cin >> nums[i] >> nums[i];
memset(dp, -1, sizeof(dp));
ll res = solve(0, 0, k, nums, n);
cout << res << endl;
return 0;
} Comments (5)
 » I don't know which problem you are referring to, but I see that you are passing the parameter vector> nums by value instead of by reference in your solve function. This means that every time you make a call to that function, the whole structure is copied, value by value. To solve this, just put an & after the type, like this: vector>& nums, and see if that gets AC.Here's a webpage that talks about passing by reference, in case you want to know more about it. It's really important.
•  » » Didn't know pass by value would cost this much. Thank you!! Got AC
 » Can you pls upload a link to the problem?
•  » » Linked
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