diff --git a/picture/printf_data.drawio.svg b/picture/printf_data.drawio.svg
new file mode 100644
index 0000000..b50790a
--- /dev/null
+++ b/picture/printf_data.drawio.svg
@@ -0,0 +1,29 @@
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+    <diagram id="u_L9P898_jSC_YZIsbOk" name="第 1 页">
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+                    <mxGeometry relative="1" as="geometry">
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+                </mxCell>
+                <mxCell id="5" value="for i = 1 to num_parts" style="rounded=1;whiteSpace=wrap;html=1;sketch=1;hachureGap=4;jiggle=2;curveFitting=1;fontFamily=Architects Daughter;fontSource=https%3A%2F%2Ffonts.googleapis.com%2Fcss%3Ffamily%3DArchitects%2BDaughter;fontSize=20;" vertex="1" parent="1">
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\ No newline at end of file