The variable 'minSum' is being referenced before having a value set to it

const arrSort: number[] = arr.sort();
let minSum: number = 0;
arrSort.forEach((a, b) => {
 if(b > 0){
   minSum += minSum + a;
   console.log(b)
 }
})
console.log(minSum); 

Even though 'minSum' is defined at the top, TypeScript still throws an error claiming it has not been assigned a value.

Answer №1

Make sure to set minSum initially in order to start accumulating the sum there. Be careful not to add the same value twice when doing minSum += minSum + a;

let arrSort: number[] = arr.sort(), minSum: number = 0;
   arrSort.forEach((a, b) => {
     if(b > 0){
       minSum += a;
       console.log(b)
     }
   })
   console.log(minSum); // Error: Variable 'minSum' is used before being assigned.

Experiment with the code snippet here

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