2016-10-23 34 views
-2
int* create_array(char category, int n){ 
    int *a; 

    a = malloc(n* sizeof(int)); 

    for (int i = 0; i < n; i++) { 
    int x; 
    srand(time(NULL)); 
    x = rand(); 
    a[i] = x; 
    } 

当我打印此代码时,它只是打印相同的随机变量'n'次。创建一个动态数组并为其分配随机整数值?

+3

这些答案可以帮助:srand函数将返回相同的值(http://stackoverflow.com/questions/14494375/srand-function-is-returning -same-values/14494428#14494428)和[为什么rand()在此for循环中使用srand(time(null))返回相同的值?](http://stackoverflow.com/questions/10644593/why-does -rand返回最相同值-使用-srandtimenull-在此结果为环/ 10644601#10644601) – Gomiero

回答

0

您可以使用srand(getpid()或者您可以指定使用x=rand()%11从0-10生成的随机数范围;

0

你可以尝试这样的事情:

#include <stdio.h> 
#include <stdlib.h> 
#include <time.h> 

int *create_array(char category, int n); 

int 
main(int argc, char const *argv[]) { 
    time_t t; 
    int *array; 
    int i, n; 
    char category; 

    srand((unsigned)time(&t)); 

    printf("Enter category: "); 
    if (scanf("%c", &category) != 1) { 
     printf("Invalid category.\n"); 
     exit(EXIT_FAILURE); 
    } 

    printf("Enter n numbers: "); 
    if (scanf("%d", &n) != 1) { 
     printf("Invalid n value.\n"); 
     exit(EXIT_FAILURE); 
    } 

    array = create_array(category, n); 

    printf("Your n random numbers between 0-10:\n"); 
    for (i = 0; i < n; i++) { 
     printf("%d ", array[i]); 
    } 

    free(array); 

    return 0; 
} 

int 
*create_array(char category, int n) { 
    int *array; 
    int i, candidate; 

    array = malloc(n * sizeof(*array)); 

    for (i = 0; i < n; i++) { 
     candidate = rand() % 10; 
     array[i] = candidate; 
    } 

    return array; 
}