String str1 = "hello world cout<<\"hi,this is Sunday\"<<endl";
int index = str1.indexOf("cout");
System.out.printf("index: %d\n", index);
String part1 = str1.substring(0, index);
String part2 = str1.substring(index);
System.out.printf("part1: %s\n", part1);
System.out.printf("part2: %s\n", part2);