1 files changed, 29 insertions, 0 deletions
diff --git a/num_digits.c b/num_digits.c
new file mode 100644
index 0000000..c25fc29
--- /dev/null
+++ b/num_digits.c
@@ -0,0 +1,29 @@
+#include<stdio.h>
+
+/*
+ * Count digits, whitespace, and other characters.
+ */
+main() {
+    int c, i, nwhite, nother;
+    int ndigit[10];
+
+    nwhite = nother = 0;
+
+    for (i = 0; i < 10; ++i)
+        ndigit[i] = 0;
+
+    while ((c = getchar()) != EOF)
+        if (c >= '0' && c <= '9')
+            ++ndigit[c - '0'];
+        else if (c == ' ' || c == '\n' || c == '\t')
+            ++nwhite;
+        else 
+            ++nother;
+
+    printf("digits =");
+
+    for (i = 0; i < 10; ++i)
+        printf(" %d", ndigit[i]);
+    printf(", whitespace = %d, other = %d\n",
+            nwhite, nother);
+}