String concatenation quadratic

Code reviewAlgorithms & data structuresMid–Senior~18 min

Review this Java method that renders a CSV line-by-line.

What a strong answer looks like

Separate real bugs from style. Rank issues by severity, point at the root cause rather than the symptom, and suggest a concrete fix, specific and kind.

0:00 of about 18 min

Mark a line and say what kind of problem it is.0 findings

1String renderCsv(List<String[]> rows) {

2 String out = "";

3 for (String[] row : rows) {

4 for (int i = 0; i < row.length; i++) {

5 out += row[i];

6 if (i < row.length - 1) out += ",";

7 }

8 out += "\n";

9 }

10 return out;

11}

Which questions mattered is sealed until you submit. Telling you now would just be handing over the edge cases.