randnum

#include <stdio.h>
#include <stdlib.h>
#include <time.h>
int main(void)
{
    FILE *fp;
    fp = fopen("randnum.txt","w");
    srand((unsigned int)time(NULL));
    int i, N, k;
    N = rand() % 9998 + 3;
    float sum, arr[10000];
    for(i=0;i<N;i++){
        fprintf(fp, "%.2f\n", ((rand() % 2001)-1000)/100.0 );
    }

    fclose(fp);

    // 読み込んで平均を出す部分
    fp = fopen("randnum.txt","r");
    k = 0;
    sum = 0.0;
    while (fscanf(fp, "%f", &arr[i]) != EOF){
        sum += arr[i];
        k++;
    }
    printf("平均は、%f\n",sum/k);

    fclose(fp);

    return 0;
}