Project Euler task 30

Surprisingly there are only three numbers that can be written as the sum of fourth powers of their digits:

1634 = 14 + 64 + 34 + 44
8208 = 84 + 24 + 04 + 84
9474 = 94 + 44 + 74 + 44
As 1 = 14 is not a sum it is not included.

The sum of these numbers is 1634 + 8208 + 9474 = 19316.

Find the sum of all the numbers that can be written as the sum of fifth powers of their digits.

================PROGRAM TEXT===============

#include

#define MYTYPE char

__global__ void findNumbers(MYTYPE* _pArray) {

int nThreadNum = blockDim.x * blockIdx.x + threadIdx.x;

int resNum = 0;

int k = nThreadNum;

for (int i = 0; i < 7; i++) {

int num = k % 10;

resNum += num * num * num * num * num;

k /= 10;

}

_pArray[nThreadNum] = (resNum == nThreadNum) ? 1 : 0;

}

int main() {

MYTYPE* d_pArray;

int threadsPerBlock = 128;

int blocksNum = 8192;

size_t nArraySize = threadsPerBlock * blocksNum * sizeof(MYTYPE);

MYTYPE* h_pArray = new MYTYPE[nArraySize];

cudaMalloc(&d_pArray, nArraySize);

cudaMemset(&d_pArray, 0, nArraySize);

// Kernel

findNumbers<<< blocksNum, threadsPerBlock >>>(d_pArray);

cudaMemcpy((void *) h_pArray, d_pArray, nArraySize, cudaMemcpyDeviceToHost);

cudaFree(d_pArray);

int res = 0;

for (int i = 0; i < nArraySize/sizeof(MYTYPE); i++) {

if (i == 1)

continue;

if (h_pArray[i] == 1) {

res += i;

std::cout << i << ": " << (int) h_pArray[i] << std::endl;

}

}

std::cout << res << std::endl;

delete [] h_pArray;

return 0;

}