Published May 16, 2022
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Given a string columnTitle that represents the column title as appear in an
Excel sheet, return its corresponding column number.
For example:
A -> 1
B -> 2
C -> 3
...
Z -> 26
AA -> 27
AB -> 28
...
Input: columnTitle = "A"
Output: 1
Input: columnTitle = "AB"
Output: 28
Input: columnTitle = "ZY"
Output: 701
1 <= columnTitle.length <= 7columnTitle consists only of uppercase English letters.columnTitle is in the range ["A", "FXSHRXW"].function titleToNumber(columnTitle: string): number {
let res = 0;
let power = 0;
const charCodeA: number = 'A'.charCodeAt(0)
for(let i = columnTitle.length - 1; i >=0; i--){
res += (26**power * (columnTitle.charCodeAt(i) - charCodeA + 1))
power++;
}
return res;
};