http://kor.i2p/books/The%20C%20Programming%20Language%20by%20K&R/chapter3.html
Here is the same program with a switch : #include < stdio.h > main() /* count digits, white space, others */
{
int c, i, nwhite, nother, ndigit[10];
nwhite = nother = 0;
for (i = 0; i < 10; i++)
ndigit[i] = 0;
while ((c = getchar()) != EOF) {
switch (c) {
case '0': case '1': case '2': case '3': case '4':
case '5': case '6': case '7': case '8': case '9':
ndigit[c-'0']++;
...