During the round Codeforces Round 407 (Div. 2) I used the following generator code to hack this solution 25904282 for this problem 789A - Anastasia and pebbles

printf("100000 1\n");
for(i=0;i<100000-1;i++)
{
    printf("%d ",10000);
}
printf("%d",10000);
printf("\n");

Unfortunately, the attempt became unsuccessful as the solution produced the output in 998 ms. Later during the system tests, the same solution gave a TLE on the exact same test case — Test Case #27

Was that just bad luck? :P