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// my linkedin : https://www.linkedin.com/in/vaalarivan-prasanna-3a07bb203/
// 1-D case
vector<int> vec(desiredVectorSize, 0);
// 2-D case
vector<vector<int>> vec(desiredNoOfRows, vector<int>(desiredNoOfColumns, 0));
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// 1-D vector
std::vector<int>> (number_of_rows, 0);
// 2-D vector
std::vector<std::vector<int>> (number_of_rows, std::vector<int>(number_of_colums, 0));