You have r red, g green and b blue balloons. To decorate a single table for the banquet you need exactly three balloons. Three balloons attached to some table shouldn't have the same color. What maximum number t of tables can be decorated if we know number of balloons of each color?
Your task is to write a program that for given values r, g and b will find the maximum number t of tables, that can be decorated in the required manner.
The single line contains three integers r, g and b (0 ≤ r, g, b ≤ 2·109) — the number of red, green and blue baloons respectively. The numbers are separated by exactly one space.
Print a single integer t — the maximum number of tables that can be decorated in the required manner.
5 4 3
4
1 1 1
1
2 3 3
2
In the first sample you can decorate the tables with the following balloon sets: "rgg", "gbb", "brr", "rrg", where "r", "g" and "b" represent the red, green and blue balls, respectively.
分析:
1、首先排序,
2.如果前两者之和的两倍小于第三者。那么个数就是前两者之和的个数
3.如果前两者之和的两倍大于第三者。我们可以这么想,先用第三者与前两者2:1平衡掉,然后前两者2:1一直走。也就是总数除以三
1 #include2 #include 3 #include 4 using namespace std; 5 int main() 6 { 7 long long a[3]; 8 scanf("%lld%lld%lld",&a[0],&a[1],&a[2]); 9 sort(a,a+3);10 if((a[0]+a[1])*2<=a[2])11 {12 printf("%d\n",a[0]+a[1]);13 }14 else15 {16 printf("%d\n",(a[0]+a[1]+a[2])/3);17 }18 }