var input = require("fs").readFileSync("input.txt").toString();
var depths = input.split("\n").filter((a)=>(a)).map((a)=>(a.split(": ").map((b)=>(parseInt(b))))).reduce((dep, a)=>{dep[a[0]] = a[1]; return dep;}, []);
var caught = (del)=>(depths.filter((a, i)=>(((i+del) % (a*2 - 2)) == 0)).length > 0);
for(var i = 0; i < 10000000; i++){
	if(caught(i) == false){
		console.log(i);
	}
}