rand函数c语言实例,C语言中随机函数发生器rand()用法举例

#if 1

#include

#include

#include

#include

#include

using namespace std;

int main()

{

int nRandNumber[10];

for (int idx = 0; idx < 10; ++idx)

{

nRandNumber[idx] = rand();//取随机数范围为integer 0 ~ RAND_MAX(32767)

cout << nRandNumber[idx] << endl;

}

for (int idx = 0; idx < 10; ++idx)

{

nRandNumber[idx] = (double)rand() / (RAND_MAX + 1) * (125 - 35) + 35;//取数35到125之间

cout << nRandNumber[idx] << endl;

}

cout << RAND_MAX << endl;//最大值是32767

//srand是一个随机数种子产生函数，当参数为1时，所得到的随机数序列一样

//output : nRanNum1 : 41 nRanNum2 : 18467

// nRanNum3 : 41 nRanNum4 : 18467

ofstream outFile("d:out.txt");

srand(1);

int nRanNum1 = rand();

int nRanNum2 = rand();

cout << "nRanNum1 : " << nRanNum1 << " nRanNum2 : " << nRanNum2 << endl;

outFile << "nRanNum1 : " << nRanNum1 << " nRanNum2 : " << nRanNum2 << endl;

srand(1);

int nRanNum3 = rand();

int nRanNum4 = rand();

cout << "nRanNum3 : " << nRanNum3 << " nRanNum4 : " << nRanNum4 << endl;

outFile << "nRanNum3 : " << nRanNum3 << " nRanNum4 : " << nRanNum4 << endl;

system("pause");

return 1;

}

#endif