Untitled

#include <iostream>
#include <cuda_runtime.h>

#define N 100
#define C 5000

__global__ void knapsack(int n, int c, int *v, int *w, int *x, int *max_value) {
    int i = blockIdx.x * blockDim.x + threadIdx.x;
    int j, k;
    int dp[N+1][C+1];
    for (j = 0; j <= c; j++) {
        dp[0][j] = 0;
    }
    for (i = 1; i <= n; i++) {
        for (j = 0; j <= c; j++) {
            if (j < w[i]) {
                dp[i][j] = dp[i-1][j];
            } else {
                dp[i][j] = max(dp[i-1][j], dp[i-1][j-w[i]] + v[i]);
            }
        }
    }
    *max_value = dp[n][c];
}

int main() {
    int n = 5; // Number of items
    int c = 10; // Knapsack capacity
    int v[] = {0, 6, 3, 5, 4, 6}; // Values of items
    int w[] = {0, 2, 2, 6, 5, 4}; // Weights of items
    int x[N+1] = {0}; // Selected items
    int max_value = 0; // Maximum value

    // Allocate memory on GPU
    int *d_v, *d_w, *d_x, *d_max_value;
    cudaMalloc((void**)&d_v, (n+1)*sizeof(int));
    cudaMalloc((void**)&d_w, (n+1)*sizeof(int));
    cudaMalloc((void**)&d_x, (N+1)*sizeof(int));
    cudaMalloc((void**)&d_max_value, sizeof(int));

    // Copy data from host to device
    cudaMemcpy(d_v, v, (n+1)*sizeof(int), cudaMemcpyHostToDevice);
    cudaMemcpy(d_w, w, (n+1)*sizeof(int), cudaMemcpyHostToDevice);
    cudaMemcpy(d_x, x, (N+1)*sizeof(int), cudaMemcpyHostToDevice);

    // Run kernel
    knapsack<<<1,1>>>(n, c, d_v, d_w, d_x, d_max_value);

    // Copy data from device to host
    cudaMemcpy(&max_value, d_max_value, sizeof(int), cudaMemcpyDeviceToHost);

    // Print result
    std::cout << "Maximum value: " << max_value << std::endl;

    // Free memory on GPU
    cudaFree(d_v);
    cudaFree(d_w);
    cudaFree(d_x);
    cudaFree(d_max_value);

    return 0;
}