Only assignment, call, increment, decrement, and new object expressions can be used as a statement???

Hi there, I have been this [tutorial][1] and seeing as I have never used C# before I have just been copying it exactly but I run into 2 errors in this code: `for(int i = 0; i < sizeX; i+) { for(int j = 0; j < sizeY; j+) { for(int k = 0; k < sizeZ; k+) {` The errors are: error CS0201: Only assignment, call, increment, decrement, and new object expressions can be used as a statement and error CS1525: Unexpected symbol `;', expecting `)', or `,' even when there is no semicolon there. any help would be appreciated a lot thank you. [1]: http://learninggeekblog.wordpress.com/2013/04/25/voxel-engine-part-1/