Simple Problem with arrays

Hello,

Ive got a little Problem with the mql4 array funktion. I want to open a chart with the ChartOpen() funktion in different timeframes . To make it easy, Iv set up an array with all the different timeframes. Then, Ive inserted it into the ChartOpen() funktion, like int the Article: ,,Mql4 for newbies Part 2". But it didn´t work. It always says: ,,x - is not declared". So here my question: How can I open a chart in different timeframes without writing the ChartOpen() funktion again and again. Thanks for your answers!!

int period[]={1,5,15,30,60,240,1440,10080,43200};
ChartOpen("EURUSD",period[x]);