1.请问各位大佬我写出的代码问题在哪里？

data1 = Import["C:\\Users\\vincen\\Desktop\\222.xlsx"]
data = Part[data1, 1]
a = Table[0, Length[data]];
b = Table[0, Length[data]];
start = "S3139";
end = "S1589";
For[i = 1, i <= Length[data], i++,
For[j = 1, j <= Length[Part[data, i]], j++,
If[start == Part[Part[data, i], j], ReplacePart[a, i -> 1]]]]
For[i = 1, i <= Length[data], i++,
For[j = 1, j <= Length[Part[data, i]], j++,
If[end == Part[Part[data, i], j], ReplacePart[b, i -> 1]]]]
For[i = 1, i <= Length[data], i++,
If[(a[i] = 1) && (b[i] = 1), Print[Part[Part[data, i], 1]]]]

求助啊各位大佬，一晚上了没看懂问题在哪...

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If[(a[i] = 1) && (b[i] = 1), Print[Part[Part[data, i], 1]]]]
(a[i] == 1) && (b[i] == 1)
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你的集合a和集合b没起作用吧
k = {a, b, c, d, e};
ReplacePart[k, 3 -> xxx]
k
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