Greg is a beginner bodybuilder. Today the gym coach gave him the training plan. All it had wasn integers a1, a2, ..., an. These numbers mean that Greg needs to do exactly n exercises today. Besides, Greg should repeat thei-th in order exercise ai times.
Greg now only does three types of exercises: "chest" exercises, "biceps" exercises and "back" exercises. Besides, his training is cyclic, that is, the first exercise he does is a "chest" one, the second one is "biceps", the third one is "back", the fourth one is "chest", the fifth one is "biceps", and so on to then-th exercise.
Now Greg wonders, which muscle will get the most exercise during his training. We know that the exercise Greg repeats the maximum number of times, trains the corresponding muscle the most. Help Greg, determine which muscle will get the most training.
Input
The first line contains integer n (1 ≤ n ≤ 20). The second line containsn integers a1, a2, ..., an(1 ≤ ai ≤ 25) — the number of times Greg repeats the exercises.
Output
Print word "chest" (without the quotes), if the chest gets the most exercise, "biceps" (without the quotes), if the biceps gets the most exercise and print "back" (without the quotes) if the back gets the most exercise.
It is guaranteed that the input is such that the answer to the problem isunambiguous.
Sample Input
Input 2 2 8 Output biceps Input 3 5 1 10 Output back Input 7 3 3 2 7 9 6 8 Output chest #include<stdio.h> int main() { int n; int i; int a[22]={0}; int num[3]={0}; int k; int max,u; scanf("%d",&n); k=0; for(i=0;i<n;i++) { if(k==0) { scanf("%d",&a[i]); num[0]+=a[i]; k++; } else if(k==1) { scanf("%d",&a[i]); num[1]+=a[i]; k++; } else { scanf("%d",&a[i]); num[2]+=a[i]; k++; } if(k==3) { k=0; } } max=num[0]; u=0; for(i=1;i<3;i++) { if(num[i]>max) { max=num[i]; u=i; } } if(u==0) printf("chest\n"); else if(u==1) printf("biceps\n"); else if(u==2) printf("back\n"); return 0; }