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void PrintProbability_Solution1(int number){ if(number < 1) return; int maxSum = number * g_maxValue; int* pProbabilities = new int[maxSum - number + 1]; for(int i = number; i <= maxSum; ++i) pProbabilities[i - number] = 0; Probability(number, pProbabilities); int total = pow((double)g_maxValue, number); for(int i = number; i <= maxSum; ++i) { double ratio = (double)pProbabilities[i - number] / total; printf("%d: %e\n", i, ratio); } delete[] pProbabilities;} void Probability(int number, int* pProbabilities){ for(int i = 1; i <= g_maxValue; ++i) Probability(number, number, i, pProbabilities);} void Probability(int original, int current, int sum, int* pProbabilities){ if(current == 1) { pProbabilities[sum - original]++; } else { for(int i = 1; i <= g_maxValue; ++i) { Probability(original, current - 1, i + sum, pProbabilities); } }}
void PrintProbability_Solution2(int number){ if(number < 1) return; int* pProbabilities[2]; pProbabilities[0] = new int[g_maxValue * number + 1]; pProbabilities[1] = new int[g_maxValue * number + 1]; for(int i = 0; i < g_maxValue * number + 1; ++i) { pProbabilities[0][i] = 0; pProbabilities[1][i] = 0; } int flag = 0; for (int i = 1; i <= g_maxValue; ++i) pProbabilities[flag][i] = 1; for (int k = 2; k <= number; ++k) { for(int i = 0; i < k; ++i) pProbabilities[1 - flag][i] = 0; for (int i = k; i <= g_maxValue * k; ++i) { pProbabilities[1 - flag][i] = 0; for(int j = 1; j <= i && j <= g_maxValue; ++j) pProbabilities[1 - flag][i] += pProbabilities[flag][i - j]; } flag = 1 - flag; } double total = pow((double)g_maxValue, number); for(int i = number; i <= g_maxValue * number; ++i) { double ratio = (double)pProbabilities[flag][i] / total; printf("%d: %e\n", i, ratio); } delete[] pProbabilities[0]; delete[] pProbabilities[1];}