diff --git a/CMakeLists.txt b/CMakeLists.txt
index 5cd50dd..3a4dbfc 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -3,7 +3,7 @@ cmake_minimum_required(VERSION 3.0)
 project(learningc LANGUAGES C)
 
 set(CHAPTER 1)
-set(EXERCISE 21)
+set(EXERCISE 22)
 
 add_executable(learningc chapters/${CHAPTER}/exercises/${EXERCISE}.c)
 
diff --git a/chapters/1/exercises/21.c b/chapters/1/exercises/21.c
index d7b141b..0f7b622 100644
--- a/chapters/1/exercises/21.c
+++ b/chapters/1/exercises/21.c
@@ -1,4 +1,4 @@
-#include<stdio.h>
+#include <stdio.h>
 #include "shared/limits.h"
 #include "shared/functions.h"
 #include "shared/functions/entab.c"
diff --git a/chapters/1/exercises/22.c b/chapters/1/exercises/22.c
new file mode 100644
index 0000000..ec40317
--- /dev/null
+++ b/chapters/1/exercises/22.c
@@ -0,0 +1,12 @@
+#include <stdio.h>
+#include "shared/functions.h"
+#include "shared/functions/fold.c"
+
+int main() {
+  int len;
+  char line[MAXLINE];
+  while ((len = fold(line,MAXLINE, 30)) > 0) {
+    printf("%s", line);
+  }
+  return 0;
+}
diff --git a/chapters/1/exercises/shared/functions.h b/chapters/1/exercises/shared/functions.h
index bc956bb..498798b 100644
--- a/chapters/1/exercises/shared/functions.h
+++ b/chapters/1/exercises/shared/functions.h
@@ -6,3 +6,4 @@ void copy(char to[], char from[]);
 int getlines(char line[], int maxline);
 int detab(char s[],int lim, int col);
 int entab(char s[], int lim, int col);
+int fold(char s[], int lim, int cpr);
diff --git a/chapters/1/exercises/shared/functions/fold.c b/chapters/1/exercises/shared/functions/fold.c
new file mode 100644
index 0000000..4062aeb
--- /dev/null
+++ b/chapters/1/exercises/shared/functions/fold.c
@@ -0,0 +1,19 @@
+#include <stdio.h>
+
+int fold(char s[], int lim, int cpr) {
+  int c, i;
+  for (i=0; i < lim-1 && i<cpr && (c=getchar())!=EOF && c!='\n';) {
+    if (i != 0 || (c != ' ' && c != '\t')) {
+      s[i] = c;
+      ++i;
+    }
+  }
+  for (;i > 0 && (s[i-1] == ' ' || s[i-1] == '\t'); i--);
+  if (i > 0) {
+    s[i] = '\n';
+    s[i+1] = '\0';
+  } else {
+    s[i] = '\0';
+  }
+  return i;
+}