模拟/字符串处理 UVALive 6833 Miscalculatio

题目传送门

 /*
     模拟/字符串处理：主要是对*的处理，先把乘的预处理后再用加法，比如说是：1+2*3+4 = 1+..6+4 = 11
 */
 #include <cstdio>
 #include <algorithm>
 #include <cstring>
 #include <string>
 #include <cmath>
 #include <vector>
 #include <map>
 #include <queue>
 using namespace std;

 typedef long long ll;
 const int MAXN = 1e2 + ;
 const int INF = 0x3f3f3f3f;
 char s[MAXN];
 int len;

 void solve(void)
 {
     int p1 = , p2 = ;
     for (int i=; i<=len; ++i)
     {
         if (s[i] == '*')
         {
             p1 = p2 = i;
             while (p1 >=  && s[p1] != '+')    p1--;    p1++;
             while (p2 <= len && s[p2] != '+')    p2++;    p2--;
             ll tmp = ;
             for (int j=p1; j<=p2; j+=)
             {
                 if (j == p1)    tmp = s[j] - '';
                 else    tmp = tmp * (s[j] - '');
             }
 //            printf ("p1: %d p2: %d\ntmp: %d\n", p1, p2, tmp);
             int p = p2;
             while (tmp)
             {
                 s[p--] = tmp %  + '';
                 tmp /= ;
             }
             for (int j=p1; j<=p; ++j)    s[j] = '.';
         }
     }
 }

 int main(void)        //UVALive 6833 Miscalculation
 {
 //    freopen ("B.in", "r", stdin);

     while (scanf ("%s", s + ) == )
     {
         ll y;    scanf ("%lld", &y);
         ll sum_l = , sum_m = ;

         len = strlen (s + );    char op;    int x = ;
         for (int i=; i<=len; ++i)
         {
             if (i & )
             {
                 if (i == )    sum_l = s[i] - '';
                 else
                 {
                     if (op == '+')    sum_l += s[i] - '';
                     else    sum_l = sum_l * (s[i] - '');
                 }
             }
             else    op = s[i];
         }

         solve ();
         for (int i=; i<=len; ++i)
         {
             if (s[i] == '.' || s[i] == '+')    continue;
             else if (s[i] >= '' && s[i] <= '')
             {
                 ll res = ;    int j;
                 for (j=i; j<=len; ++j)
                 {
                     if (s[j] == '+')    break;
                     res = res *  + (s[j] - '');
                 }
                 sum_m += res;
                 i = j - ;
             }
         }

         if (y == sum_l && y == sum_m)    puts ("U");
         else if (y != sum_l && y != sum_m)    puts ("I");
         else
         {
             if (y == sum_l)    puts ("L");
             else    puts ("M");
         }

 //        printf ("%s\n", s + 1);
 //        printf ("%lld %lld \n", sum_l, sum_m);
     }

     return ;
 }