React Js Parsing error: Legacy octal literals are not allowed in strict mode

Question

i'am new to React Js , i have a form where i get a string from the user, i split this string into spaces , then i save it in my state variable this code works fine :

  handleSubmit(event) {
    event.preventDefault();


    let products = this.state.newProducts;

    //split the string into an array
    var string = this.state.QrCode.split(" ");

    // check all the string in the form if the Qr match an exsitant => save it 
    for(var i =0; i < string.length; i++){    // fetch the entery 
      this.state.smth.map(prd =>  {           // fetch the database
        if(prd.Qr==string[i]){                // verification 
            products.push({
              id: prd.id,
              Qr: prd.Qr,
              Stat: prd.Stat,
              name: prd.name
            });

        }

      }

      )
    }


      // save it in newProducts
    this.setState({
      newProducts: products
    });

    // refresh the grid
    this.grid.refresh();
  }

then i simply tried to add variable to push a data in the array if it doest exist "smth" , but am getting this error : Parsing error: Legacy octal literals are not allowed in strict mode.

  handleSubmit(event) {
    event.preventDefault();
    let hasChanged = 0;

    let products = this.state.newProducts;

    //split the string into an array
    var string = this.state.QrCode.split(" ");

    // check all the string in the form if the Qr match an exsitant => save it 
    for(var i =0; i < string.length; i++){    // fetch the entery 
      this.state.smth.map(prd =>  {           // fetch the database
        if(prd.Qr==string[i]){                // verification 
          hasChanged=1;
            products.push({
              id: prd.id,
              Qr: prd.Qr,
              Stat: prd.Stat,
              name: prd.name
            });

        }
        if(hasChanged==0){
          products.push({
            id: 00,
            Qr: string[i],
            Stat: "unknown",
            name: "XXXX"
          });
        }

      }

      )
    }


      // save it in newProducts
    this.setState({
      newProducts: products
    });

    // refresh the grid
    this.grid.refresh();
  }

so the 1st code works fine , but it doest add the no matching string and thats what i want to add hope i can get some help . thank you.