n=int(input())
a=list(map(int,input().split()))
s=sorted(list(set(a)))
if len(s)<=1:
print("NO")
else:
print(s[1])
#include <cstdio>
int main(){
int temp(0), currentMin(101), secondMin(101);
int n; scanf("%d", &n);
while(n--){
scanf("%d", &temp);
if(temp < currentMin){secondMin = currentMin; currentMin = temp;}
else if (currentMin < temp && temp < secondMin){secondMin = temp;}
}
if(secondMin == currentMin || secondMin == 101){puts("NO");}
else{printf("%d\n", secondMin);}
return 0;
}1633C - Kill the Monster | 1611A - Make Even |
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