Go: package main

import (
	"bufio"
	"os"
	"strconv"
	"fmt"
)

var scanner = bufio.NewScanner(os.Stdin)

func nextInt() int {
	scanner.Scan()
	i, e := strconv.Atoi(scanner.Text())
	if e != nil {
		panic(e)
	}
	return i
}

func zeller(month, day int) int {
	year := 2004
	if month == 1 || month == 2 {
		year--
		month += 12
	}
	return (year + year/4 - year/100 + year/400 + (13*month+8)/5 + day)%7
}

func main() {
	scanner.Split(bufio.ScanWords)
	for {
		month := nextInt()
		day := nextInt()
		if month == 0 && day == 0{
			break
		}
		switch zeller(month, day) {
		case 0:
			fmt.Println("Sunday")
		case 1:
			fmt.Println("Monday")
		case 2:
			fmt.Println("Tuesday")
		case 3:
			fmt.Println("Wednesday")
		case 4:
			fmt.Println("Thursday")
		case 5:
			fmt.Println("Friday")
		case 6:
			fmt.Println("Saturday")
		}
	}
}

C++: #include <bits/stdc++.h>

using namespace std;

template<class T> inline T sqr(T x) {return x*x;}

typedef vector<int> VI;
typedef vector<VI> VVI;
typedef vector<string> VS;
typedef pair<int, int> PII;
typedef long long LL;
typedef unsigned long long ULL;

#define ALL(a)  (a).begin(),(a).end()
#define RALL(a) (a).rbegin(), (a).rend()
#define PB push_back
#define MP make_pair
#define SZ(a) int((a).size())
#define EACH(i,c) for(typeof((c).begin()) i=(c).begin(); i!=(c).end(); ++i)
#define EXIST(s,e) ((s).find(e)!=(s).end())
#define SORT(c) sort((c).begin(),(c).end())

#define FOR(i,a,b) for(int i=(a);i<(b);++i)
#define REP(i,n)  FOR(i,0,n)

const double EPS = 1e-10;
const double PI  = acos(-1.0);

#define CLR(a) memset((a), 0 ,sizeof(a))

int dx[4] = {-1, 0, 1, 0};
int dy[4] = {0, -1, 0, 1};

int main() {
  int k,m,d;
  string today[7]={"Monday","Tuesday","Wednesday","Thursday","Friday","Saturday","Sunday"};
  int mon[12]={31,29,31,30,31,30,31,31,30,31,30,31};

  while(cin >>m>>d){
    if(m==0&&d==0)break;

    for(int i=0;m-1>i;i++){
      if(m==1)break;
      else d+=mon[i];

  }
    k=d%7+2;
    cout <<today[k]<<endl;
  
  }
}

C++: #include<stdio.h>
int main(void)
{
	int y,m,d;
	int i;
	int ans;
	
	y=2004;
	
	for(;;)
	{
		scanf("%d%d",&m,&d);
		if(m==0 && d==0)
			break;
		
		ans=0;
		
		ans=(y-1)*365+y/4-y/100+y/400;
		
		for(i=1;i<m;i++)
		{
			if(i==2 && (y/4==0 && y/100!=0) || y/400==0)
				ans+=29;
			else if(i==2)
				ans+=28;
			else if(i<8 && i%2==0)
				ans+=30;
			else if(i<8 && i%2!=0)
				ans+=31;
			else if(i>7 && i%2==0)
				ans+=30;
			else
				ans+=31;
		}
		
		ans+=d;
		
		if(m<3 && ((y%4==0 && y%100!=0) || y%400==0))
			ans-=1;
		
		switch(ans%7)
		{
			
			case 0:
				printf("Sunday\n");
				break;
			case 1:
				printf("Monday\n");
				break;
			case 2:
				printf("Tuesday\n");
				break;
			case 3:
				printf("Wednesday\n");
				break;
			case 4:
				printf("Thursday\n");
				break;
			case 5:
				printf("Friday\n");
				break;
			case 6:
				printf("Saturday\n");
				break;
		}
	}
		
	return 0;
}

C++: #include <iostream>
#include <vector>
#include <list>
#include <map>
#include <set>
#include <stack>
#include <queue>
#include <bitset>
#include <algorithm>
#include <numeric>
#include <utility>
#include <sstream>
#include <iomanip>
#include <cstdio>
#include <cmath>
#include <string>
#include <cstring>
#include <climits>
 
#define REP(i,b,n) for(int i=b;i<n;++i)
#define REPR(i,b,n) for(int i=n-1;i>=b;--i)
#define CLR(mat) memset(mat, 0, sizeof(mat))
#define NCLR(mat) memset(mat, -1, sizeof(mat))
#define EACH(i, c) for(typeof((c).begin()) i = (c).begin(); i != (c).end(); ++i)
#define EXIST(s, e) ((s).find(e) != (s).end())
#define BIT(n, b) ((n>>b) & 1)
#define PI acos(-1.0)

using namespace std;

static const double EPS = 1e-9;
typedef pair<int, int> pii;
typedef long long ll;

int mday[] = {0, 31, 29, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31};
string week[] = {"Monday", "Tuesday", "Wednesday", "Thursday", "Friday", "Saturday", "Sunday"};

int main(){
		
	int m, d;
	
	while(cin>>m>>d, (m||d)){
		
		int dsum = 3;
		
		for(int i = 0; i < m; ++i){
			dsum += mday[i];
		}
		
		cout << week[dsum%7] << endl;
	}
	
	return 0;
}

C++: #include <iostream>
using namespace std;


int main()
{
	int m, d;
	while (cin >> m >> d, m || d){
		int day = 0;
		for (int i = 1; i < m; i++){
			if (i == 2){
				day += 29;
			}
			else if (i == 4 || i == 6 || i == 9 || i == 11){
				day += 30;
			}
			else{
				day += 31;
			}
		}
		day += d;
		if (day % 7 == 1){
			cout << "Thursday" << endl;
		}
		else if (day % 7 == 2){
			cout << "Friday" << endl;
		}
		else if (day % 7 == 3){
			cout << "Saturday" << endl;
		}
		else if (day % 7 == 4){
			cout << "Sunday" << endl;
		}
		else if (day % 7 == 5){
			cout << "Monday" << endl;
		}
		else if (day % 7 == 6){
			cout << "Tuesday" << endl;
		}
		else{
			cout << "Wednesday" << endl;
		}
	}
	return 0;
}

C++: #include<iostream>
using namespace std;
void daysel(int x){
  switch(x % 7){
  case 6:
  cout << "Tuesday"<<endl; break;
  case 7:
  cout <<"Wednesday"<<endl;  break;
  case 1:
  cout <<"Thursday"<<endl;  break;
  case 2:
  cout <<"Friday"<<endl;  break;
  case 3:
  cout <<"Saturday"<<endl;  break;
  case 4:
  cout <<"Sunday"<<endl;  break;
  case 5:
  cout <<"Monday"<<endl;  break;
  }
}
void daycal(int month,int day){
  int x;
  switch(month){
  case 1:
  x = day; break;
  case 2:
  x = 31 + day; break;
  case 3:
  x = 60 + day; break;
  case 4:
  x = 91 + day; break;
  case 5:
  x = 121 + day; break;
  case 6:
  x = 152 + day; break;
  case 7:
  x = 182 + day; break;
  case 8:
  x = 213 + day; break;
  case 9: 
  x = 244 + day;break;
  case 10:
  x = 274 + day;break;
  case 11: 
  x = 305 + day; break;
  case 12:
  x = 335 + day; break;
  }
  daysel(x);

    }
int main(){
  int month,day;
  while(cin >> month >> day){
    if(month == 0){
      return 0;
    }
      daycal(month,day);
  }  
  
}

C++: #include <bits/stdc++.h>
#define rep(i, a, n) for(int i = a; i < n; i++)
#define repb(i, a, b) for(int i = a; i >= b; i--)
#define all(a) a.begin(), a.end()
#define o(a) cout << a << endl
#define int long long
#define first first
#define second se
using namespace std;
typedef pair<int, int> P;
typedef vector<int> vi;

int ds[13] = {0, 1, -1, 1, 0, 1, 0, 1, 1, 0, 1, 0, 1};
string st[7] =  {"Monday",
                "Tuesday",
                "Wednesday",
                "Thursday",
                "Friday",
                "Saturday",
                "Sunday"};

signed main(){
    int m, d;
    while(cin >> m >> d){
        if(m + d == 0) break;
        int s = 30 * (m - 1) + d;
        rep(i, 1, m){
            s += ds[i];
        }
        s = (s + 2) % 7;
        o(st[s]);
    }
}

C++: #include <iostream>
#include <string>
#include <vector>

using namespace std;
string a[7] = {"Monday","Tuesday","Wednesday","Thursday","Friday","Saturday","Sunday"};
int main(void){
  int aa,b;
  int mon[12] = {31,28,
		 31,30,
		 31,30,
		 31,31,
		 30,31,
		 30,31};
  while(cin>>aa>>b,aa+b){
    int d = b;
    for(int i = 0 ; i < aa-1 ; i ++){
      d += mon[i];
      //cout<<d<<endl;
    }

    cout<<a[(d+2)%7]<<endl;
  }
  //*/
}

C++: #include<iostream>
using namespace std;
int main(){
  
  int a,b;
  cin >> a >> b;
  while(a != 0){
    
    for(int i = 1;i < a;i++){
      if(i == 2){
	b += 29;
      }
      else if(i%2 == 0 && i != 8 && i != 12){
	b += 30;
      }
      else if(i == 9 || i == 11){
	b += 30;
      }
      else {
	b += 31;
      }
    }

    if(b%7 == 1) cout << "Thursday" << endl;
    else if(b%7 == 2) cout << "Friday" << endl;
    else if(b%7 == 3) cout << "Saturday" << endl;
    else if(b%7 == 4) cout << "Sunday" << endl;
    else if(b%7 == 5) cout << "Monday" << endl;
    else if(b%7 == 6) cout << "Tuesday" << endl;
    else cout << "Wednesday" << endl;
    cin >> a >> b;
  }
  return (0);
}