Question

How to sum all the unique numbers in array with TypeScript

Answer 1

const sumUniqueNumbers = (arr: number[]) => {
    let result: number = 0;
    
    for (let i: number = 0; i < arr.length; i++) {
        if (arr.indexOf(arr[i]) !== arr.lastIndexOf(arr[i])) {
            continue;
        };
        result += arr[i];
    };
    
    return result;
};

const arr: number[] = [2, 3, 4, 2, 1, 1, 7, 5, 8, 9, 5, 3];

// 4 + 7 + 8 + 9 = 28

console.log(sumUniqueNumbers(arr));



/*
run:

28

*/

 

70+ SQL courses for beginners and professionals