Problem:
Score : 100 points

Problem Statement

There are three airports A, B and C, and flights between each pair of airports in both directions.

A one-way flight between airports A and B takes P hours, a one-way flight between airports B and C takes Q hours, and a one-way flight between airports C and A takes R hours.

Consider a route where we start at one of the airports, fly to another airport and then fly to the other airport.

What is the minimum possible sum of the flight times?

Constraints

1 \leq P,Q,R \leq 100

All values in input are integers.

Input

Input is given from Standard Input in the following format:

P Q R

Output

Print the minimum possible sum of the flight times.

Sample Input 1

1 3 4

Sample Output 1

4

The sum of the flight times in the route A \rightarrow B \rightarrow C: 1 + 3 = 4 hours

The sum of the flight times in the route A \rightarrow C \rightarrow C: 4 + 3 = 7 hours

The sum of the flight times in the route B \rightarrow A \rightarrow C: 1 + 4 = 5 hours

The sum of the flight times in the route B \rightarrow C \rightarrow A: 3 + 4 = 7 hours

The sum of the flight times in the route C \rightarrow A \rightarrow B: 4 + 1 = 5 hours

The sum of the flight times in the route C \rightarrow B \rightarrow A: 3 + 1 = 4 hours

The minimum of these is 4 hours.

Sample Input 2

3 2 3

Sample Output 2

5

Solution in Go (1.6) (judge verdict: Accepted)

package main

import (
	"fmt"
)

func COM(n, k int64) int64 {
	r := int64(1)
	for i := int64(0); i < k; i++ {
		r = ModMul(r, n-i)
		r = ModDiv(r, i+1)
	}

	return r
}

const (
	MOD = 1000000000 + 7
)

func ModAdd(a, b int64) int64 {
	return (a + b) % MOD
}

func ModMul(a, b int64) int64 {
	return a * b % MOD
}

func ModSub(a, b int64) int64 {
	r := (a%MOD - b%MOD) % MOD
	if r < 0 {
		r += MOD
	}
	return r
}

func ModDiv(a, b int64) int64 {
	return a % MOD * ModInv(b) % MOD
}

func ModPow(a, n int64) int64 {
	var r int64 = 1
	for n > 0 {
		if n&1 == 1 {
			r = r * a % MOD
		}
		a = a * a % MOD
		n >>= 1
	}
	return r
}

func ModInv(a int64) int64 {
	var b, u, v int64 = MOD, 1, 0
	for b > 0 {
		t := a / b
		a -= t * b
		a, b = b, a
		u -= t * v
		u, v = v, u
	}
	u %= MOD
	if u < 0 {
		u += MOD
	}
	return u
}

type Q struct {
	value int
	index int
	A, B  int
}

type QS []*Q

func (p QS) Len() int           { return len(p) }
func (p QS) Less(i, j int) bool { return p[i].value > p[j].value }
func (pq QS) Swap(i, j int) {
	pq[i], pq[j] = pq[j], pq[i]
	pq[i].index = i
	pq[j].index = j
}

func (pq *QS) Push(x interface{}) {
	n := len(*pq)
	item := x.(*Q)
	item.index = n
	*pq = append(*pq, item)
}

func (pq *QS) Pop() interface{} {
	old := *pq
	n := len(old)
	item := old[n-1]
	old[n-1] = nil  // avoid memory leak
	item.index = -1 // for safety
	*pq = old[0 : n-1]
	return item
}

func FactoredPrimeNumber(num int) map[int]int {
	m := map[int]int{}
	return factor(m, num, 2)
}

func factor(result map[int]int, num, pnum int) map[int]int {
	if pnum*pnum > num {
		if num != 1 {
			result[num] += 1
		}
		return result
	}

	if num%pnum == 0 {
		num /= pnum
		result[pnum]++
	} else {
		pnum++
	}
	return factor(result, num, pnum)
}

func GCD(a, b int64) int64 {
	if b == 0 {
		return a
	}
	return GCD(b, a%b)
}

func LCM(a, b int64) int64 {
	return a * b / GCD(a, b)
}

func main() {
	var A, B, C int
	fmt.Scanf("%d %d %d\n", &A, &B, &C)
	min := A + B
	if min > B+C {
		min = B + C
	}
	if min > C+A {
		min = C + A
	}

	fmt.Println(min)
}

func Reverse(runes []rune) []rune {
	for i, j := 0, len(runes)-1; i < j; i, j = i+1, j-1 {
		runes[i], runes[j] = runes[j], runes[i]
	}
	return runes
}