Knapsack dp

#include<stdio.h>
int max(int a, int b)
{
    if(a>b)
    {
        return a;
    }
    else
    {
        return b;
    }
}
int main()
{
    int val[] = {20, 25, 40}, wt[] = {25, 20, 30}, W = 50, i, j;
    int n = sizeof(val)/sizeof(val[0]);
    int knap[n+1][W+1];
    for (i = 0; i <= n; i++)
    {
        for (j = 0; j <= W; j++)
        {
            if (i==0 || j==0)
            {
                knap[i][j] = 0;
            }

            else if (wt[i-1] <= j)
            {
                knap[i][j] = max(val[i-1] + knap[i-1][j-wt[i-1]], knap[i-1][j]);
            }
            else
            {
                knap[i][j] = knap[i-1][j];
            }
        }
    }
    printf("The solution is : %d", knap[n][W]);
}