Vowels count from string

#include <stdio.h>
int main()
{
    char line[150];
    int vowels;

    vowels = 0;

    printf("Enter a line of string: ");
    fgets(line, sizeof(line), stdin);

    for (int i = 0; line[i] != '\0'; ++i)
    {
        if (line[i] == 'a' || line[i] == 'e' || line[i] == 'i' ||
            line[i] == 'o' || line[i] == 'u' || line[i] == 'A' ||
            line[i] == 'E' || line[i] == 'I' || line[i] == 'O' ||
            line[i] == 'U')
            {
             ++vowels;
            }
    }