CodeForces 732C Sanatorium (if-else)

题意：某人去旅游，记录了一共吃了多少顿饭，早中晚，但是有可能缺少，问你最少缺少了多少顿。

析：每把三个数排序，然后再一一对比，肯定是以最大数为主，其他两个肯定是缺少了。

代码如下：

#pragma comment(linker, "/STACK:1024000000,1024000000")

#include <cstdio>

#include <string>

#include <cstdlib>

#include <cmath>

#include <iostream>

#include <cstring>

#include <set>

#include <queue>

#include <algorithm>

#include <vector>

#include <map>

#include <cctype>

#include <cmath>

#include <stack>

#define freopenr freopen("in.txt", "r", stdin)

#define freopenw freopen("out.txt", "w", stdout)

using namespace std;

typedef long long LL;

typedef pair<int, int> P;

const int INF = 0x3f3f3f3f;

const double inf = 0x3f3f3f3f3f3f;

const double PI = acos(-1.0);

const double eps = 1e-8;

const int maxn = 500 + 5;

const int mod = 1e9 + 7;

const int dr[] = {-1, 1, 0, 0};

const int dc[] = {0, 0, 1, -1};

const char *de[] = {"0000", "0001", "0010", "0011", "0100", "0101", "0110", "0111", "1000", "1001", "1010", "1011", "1100", "1101", "1110", "1111"};

int n, m;

const int mon[] = {0, 31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31};

const int monn[] = {0, 31, 29, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31};

inline int Min(int a, int b){ return a < b ? a : b; }

inline int Max(int a, int b){ return a > b ? a : b; }

inline LL Min(LL a, LL b){ return a < b ? a : b; }

inline LL Max(LL a, LL b){ return a > b ? a : b; }

inline bool is_in(int r, int c){

    return r >= 0 && r < n && c >= 0 && c < m;

}

int main(){

    LL a, b, c;

    while(cin >> a >> b >> c){

        LL ans;

        if(a < b)  swap(a, b);

        if(a < c)  swap(a, c);

        if(b < c)  swap(b, c);

        if(a > b)  ans = a - b + a - c - 2;

        else if(a == b && b > c)  ans = a - c - 1;

        else ans = 0;

        cout << ans << endl;

    }

    return 0;

}