7.5: initial commit, 4.10 with scanf instead of getchar

1 files changed, 32 insertions, 0 deletions

diff --git a/7.5/op.c b/7.5/op.c
new file mode 100644
index 0000000..e7640e6
--- /dev/null
+++ b/7.5/op.c
@@ -0,0 +1,32 @@
+#include <stdio.h>
+#include <ctype.h>
+#include "op.h"
+
+char getop(char *op, size_t len)
+{
+	size_t i;
+
+	*op = '\0'; // if scanf fails
+	do {
+		scanf("%c", op);
+	} while (isblank(*op));
+
+	if (!isdigit(*op))
+		return *op;
+
+	i = 1;
+	do {
+		scanf("%c", op + i);
+	} while (isdigit(op[i]) && ++i < len);
+
+	if (op[i] == '.') {
+		i++;
+		do {
+			scanf("%c", op + i);
+		} while (isdigit(op[i]) && ++i < len);
+	}
+
+	ungetc(op[i], stdin);
+	op[i] = '\0';
+	return NUM;
+}