func_code_string: #include <bits/stdc++.h>   using namespace std;   int d[101], t, m, c, b, i, j, k, l;   string s;   int main() {     cin >> t >> m;     for (k = 0; k < t; k++) {       cin >> s;       if (s[0] ==  a ) {         cin >> c;         for (i = 0, j = -1; i < m; i++)           if (i - j == c && !d[i])             break;           else if (d[i])             j = i;         if (i - j == c && i < m) {           cout << ++b << endl;           for (l = j + 1; l <= i; l++) d[l] = b;         } else           cout <<  NULL  << endl;       } else if (s[0] ==  e ) {         cin >> c;         for (i = 0, j = 0; i < m; i++)           if (d[i] == c && c != 0) d[i] = 0, j = 1;         if (!j) cout <<  ILLEGAL_ERASE_ARGUMENT  << endl;       } else if (s[0] ==  d )         for (i = 0, j = 0; i < m; i++)           if (d[i]) l = d[j], d[j] = d[i], d[i] = l, j++;     }     return 0;   }   