func_code_string: #include <bits/stdc++.h>   using namespace std;   int n, r;   int v[100], cnt, diff;   const int inf = 0x3fffffff;   int calc(int x, int y) {     cnt = 0;     int sum = 0;     while (x) {       if (y % x == 0) {         if (y == 1)           v[++cnt] = y / x;         else if (x == 1)           v[++cnt] = y / x - 1;         else           return inf;       } else         v[++cnt] = y / x;       sum += v[cnt];       int t = y - v[cnt] * x;       y = x;       x = t;     }     if (sum != n) return inf;     diff = 0;     for (int i = 1; i <= cnt; i++)       if (v[i] != 1) diff += v[i] - 1;     return diff;   }   int ans[100], ansc;   int main() {     while (scanf( %d %d , &n, &r) != EOF) {       if (r == 0) {         if (n == 1)           printf( 0 nT n );         else           puts( IMPOSSIBLE );         continue;       }       int ret = inf;       for (int i = 1; i <= r; i++) {         int now = calc(i, r);         if (ret > now) {           ret = now;           ansc = cnt;           for (int j = 1; j <= cnt; j++) ans[j] = v[j];         }       }       if (ret == inf)         puts( IMPOSSIBLE );       else {         printf( %d n , ret);         char c =  T ;         for (int i = ansc; i >= 1; i--) {           while (ans[i]--) putchar(c);           if (c ==  T )             c =  B ;           else             c =  T ;         }         puts(  );       }     }     return 0;   }   