diff --git a/Makefile b/Makefile
index 2a395e6..3184a37 100644
--- a/Makefile
+++ b/Makefile
@@ -6,7 +6,7 @@
 #    By: tmaze <tmaze@student.42.fr>                +#+  +:+       +#+         #
 #                                                 +#+#+#+#+#+   +#+            #
 #    Created: 2018/04/07 12:47:06 by tmaze             #+#    #+#              #
-#    Updated: 2018/04/07 12:47:09 by tmaze            ###   ########.fr        #
+#    Updated: 2018/04/07 15:01:14 by tmaze            ###   ########.fr        #
 #                                                                              #
 #******************************************************************************#
 
@@ -52,7 +52,8 @@ SRCS =	\
 		ft_strclr.c   \
 		ft_striter.c  \
 		ft_striteri.c \
-		ft_strmap.c
+		ft_strmap.c   \
+		ft_strmapi.c
 OBJS = $(SRCS:.c=.o)
 INCLS = -I.
 
diff --git a/ft_strmap.c b/ft_strmap.c
index 3dfda7a..58da08a 100644
--- a/ft_strmap.c
+++ b/ft_strmap.c
@@ -5,8 +5,8 @@
 /*                                                    +:+ +:+         +:+     */
 /*   By: tmaze <tmaze@student.42.fr>                +#+  +:+       +#+        */
 /*                                                +#+#+#+#+#+   +#+           */
-/*   Created: 2018/04/07 12:35:16 by tmaze             #+#    #+#             */
-/*   Updated: 2018/04/07 13:04:23 by tmaze            ###   ########.fr       */
+/*   Created: 2018/04/07 14:57:22 by tmaze             #+#    #+#             */
+/*   Updated: 2018/04/07 15:00:12 by tmaze            ###   ########.fr       */
 /*                                                                            */
 /* ************************************************************************** */
 
diff --git a/ft_strmapi.c b/ft_strmapi.c
new file mode 100644
index 0000000..db43e65
--- /dev/null
+++ b/ft_strmapi.c
@@ -0,0 +1,27 @@
+/* ************************************************************************** */
+/*                                                                            */
+/*                                                        :::      ::::::::   */
+/*   ft_strmapi.c                                       :+:      :+:    :+:   */
+/*                                                    +:+ +:+         +:+     */
+/*   By: tmaze <tmaze@student.42.fr>                +#+  +:+       +#+        */
+/*                                                +#+#+#+#+#+   +#+           */
+/*   Created: 2018/04/07 15:00:23 by tmaze             #+#    #+#             */
+/*   Updated: 2018/04/07 15:00:24 by tmaze            ###   ########.fr       */
+/*                                                                            */
+/* ************************************************************************** */
+
+#include "libft.h"
+
+char	*ft_strmapi(char const *s, char (*f)(unsigned int, char))
+{
+	char	*ret;
+	size_t	i;
+	size_t	s_len;
+
+	i = -1;
+	s_len = ft_strlen(s);
+	ret = ft_strnew(s_len);
+	while (++i < s_len)
+		ret[i] = (*f)(i, s[i]);
+	return (ret);
+}