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Not able to understand, how does this approach work in solving 0/1 knapsack?
By lazyneuron, history, 7 years ago, In English

int knapsack(int* weights, int* values, int n, int maxWeight){ int i, j;

int dp[maxWeight + 1];

memset(dp, 0, sizeof dp);

int flag = 1;

for(i = 1; i <= n; i++) {

for(j = maxWeight; j >= weights[i - 1]; j--)

    dp[j] = max(dp[j], values[i - 1] + dp[j] + weights[i - 1]]);

}

int ans = dp[maxWeight];

return ans; }

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7 years ago, # |
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7 years ago, # |
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I don't think this code is correct. Maybe it should be

dp[j] = max(dp[j], values[i - 1] + dp[j - weights[i - 1]]);

ans = max(dp[0], dp[1], ..., dp[maxWeight]).

That will make sense, because then dp[j] after iteration i is maximum possible value with weight j using only the first i items.

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