C/C++编程产生指定范围内的随机数,直接上个小程序:
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#include <stdlib.h>
#include <time.h>
#include <stdio.h>
#include <string>
#include <string.h>
/*
* 获取随机数
* return : 随机数
*/
int commonGetRandNumber( const int low, const int high)
{
int randNum = 0;
//生成随机数
randNum = rand () % (high - low + 1) + low;
return randNum;
}
#define RAND_MAX_LEN (16)
#define RAND_MIN_VALUE (0)
#define RAND_MAX_VALUE (9999)
/*
* 获取随机数的字符串形式
* return : 随机数字符串
*/
std::string commonGetRandString()
{
int low = RAND_MIN_VALUE;
int high = RAND_MAX_VALUE;
int randNum = 0;
char randArray[RAND_MAX_LEN] = {0};
std::string randStr;
//生成随机数
srand ( time (0));
randNum = commonGetRandNumber(low, high);
snprintf(randArray, sizeof (randArray)-1, "%d" , randNum);
randStr = randArray;
return randStr;
}
/*
* 获取根据给定字符数组和随机数生成随机字符串
*/
std::string getNonceStr( int length = 32)
{
std::string chars = "abcdefghijklmnopqrstuvwxyz0123456789" ;
std::string str = "" ;
//生成随机数
srand ( time (0));
for ( int i = 0; i < length; i++ )
{
str += chars.substr(commonGetRandNumber(0, chars.size() - 1), 1);
}
return str;
}
int main()
{
//获取随机数
srand ( time (0));
int randNum = commonGetRandNumber(10, 100);
printf ( "randNum=%d\n" , randNum);
//获取随机数的字符串形式
std::string randStr = commonGetRandString();
printf ( "randStr=%s\n" , randStr.c_str());
//获取根据给定字符数组和随机数生成随机字符串
std::string randChar = getNonceStr();
printf ( "randChar=%s\n" , randChar.c_str());
}
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调用rand()会产生[0,32757]之间的随机数,(high - low)的绝对值不能超过32767。
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原文链接:https://blog.csdn.net/u011857683/article/details/81155279