text: function solve(n, m) {
      let num1 = Number(n); // let sum = +n;
      let num2 = Number(m);
  
      let result = 0;
  
      for (let i=num1; i<=num2; i++){
          result += i;
      }
  
      return result;
  }
  
  console.log(solve('1', '5'));