func_code_string: #include <bits/stdc++.h>   using namespace std;   const int maxn = 110;   int n, m;   string s;   int a[maxn];   int main() {     cin >> n >> m;     int cnt = 0;     while (n--) {       cin >> s;       if (s[0] ==  a ) {         int x;         cin >> x;         int num = 0;         bool flag = false;         for (int i = 1; i + x - 1 <= m; i++) {           num = 0;           for (int j = i; j <= i + x - 1; j++) {             if (a[j] == 0) num++;           }           if (num == x) {             cnt++;             flag = true;             for (int j = i; j <= i + x - 1; j++) a[j] = cnt;             cout << cnt << endl;             break;           }         }         if (!flag) cout <<  NULL  << endl;       } else if (s[0] ==  e ) {         int x;         cin >> x;         if (x <= 0)           cout <<  ILLEGAL_ERASE_ARGUMENT  << endl;         else {           bool flag = false;           for (int i = 1; i <= m; i++) {             if (a[i] == x) {               a[i] = 0;               flag = true;             }           }           if (!flag) cout <<  ILLEGAL_ERASE_ARGUMENT  << endl;         }       } else {         int k = 1;         for (int i = 1; i <= m; i++) {           if (a[i]) {             a[k++] = a[i];           }         }         for (; k <= m; k++) a[k] = 0;       }     }     return 0;   }   