Problem:
Score : 100 points

Problem Statement

Given is a string S representing the day of the week today.

S is SUN, MON, TUE, WED, THU, FRI, or SAT, for Sunday, Monday, Tuesday, Wednesday, Thursday, Friday, and Saturday, respectively.

After how many days is the next Sunday (tomorrow or later)?

Constraints

S is SUN, MON, TUE, WED, THU, FRI, or SAT.

Input

Input is given from Standard Input in the following format:

S

Output

Print the number of days before the next Sunday.

Sample Input 1

SAT

Sample Output 1

1

It is Saturday today, and tomorrow will be Sunday.

Sample Input 2

SUN

Sample Output 2

7

It is Sunday today, and seven days later, it will be Sunday again.

Solution in C (GCC 5.4.1) (judge verdict: Wrong Answer)

#include<stdio.h>

int cal(int A, int B, long int X, int r, int l){

    int digit =  0;
    int integer = (r + l) / 2;

    while(integer > 0){

        integer /= 10;
        digit += 1;
    }

    if(A*((r + l) / 2) + B*digit <= X){
        return 1;
    }else if(A*((r + l) / 2) + B*digit > X){
        return 0;
    }
}

int solve(int A, int B, long int X){

    int l = 0;
    int r = 1000000000;

    while(r != l){

        if(cal(A, B, X, r, l) == 1){
            l = (r + l) / 2 + 1;
        }else if(cal(A, B, X, r, l) == 0){
            r = (r + l) / 2;
        }
    }

    return l;
}

int main(void){

    int A, B;
    long int X;

    scanf("%d %d %ld", &A, &B, &X);

    printf("%ld", solve(A, B, X));
}