Problem: In this problem, we consider a simple programming language that has only declarations of one- dimensional integer arrays and assignment statements. The problem is to find a bug in the given program.

The syntax of this language is given in BNF as follows:

<image>

where <new line> denotes a new line character (LF).

Characters used in a program are alphabetical letters, decimal digits, =, [, ] and new line characters. No other characters appear in a program.

A declaration declares an array and specifies its length. Valid indices of an array of length n are integers between 0 and n - 1, inclusive. Note that the array names are case sensitive, i.e. array a and array A are different arrays. The initial value of each element in the declared array is undefined.

For example, array a of length 10 and array b of length 5 are declared respectively as follows.


a[10]
b[5]


An expression evaluates to a non-negative integer. A <number> is interpreted as a decimal integer. An <array_name> [<expression>] evaluates to the value of the <expression> -th element of the array. An assignment assigns the value denoted by the right hand side to the array element specified by the left hand side.

Examples of assignments are as follows.


a[0]=3
a[1]=0
a[2]=a[a[1]]
a[a[0]]=a[1]


A program is executed from the first line, line by line. You can assume that an array is declared once and only once before any of its element is assigned or referred to.

Given a program, you are requested to find the following bugs.

* An index of an array is invalid.
* An array element that has not been assigned before is referred to in an assignment as an index of array or as the value to be assigned.



You can assume that other bugs, such as syntax errors, do not appear. You can also assume that integers represented by <number>s are between 0 and 231 - 1 (= 2147483647), inclusive.



Input

The input consists of multiple datasets followed by a line which contains only a single '.' (period). Each dataset consists of a program also followed by a line which contains only a single '.' (period). A program does not exceed 1000 lines. Any line does not exceed 80 characters excluding a new line character.

Output

For each program in the input, you should answer the line number of the assignment in which the first bug appears. The line numbers start with 1 for each program. If the program does not have a bug, you should answer zero. The output should not contain extra characters such as spaces.

Example

Input

a[3]
a[0]=a[1]
.
x[1]
x[0]=x[0]
.
a[0]
a[0]=1
.
b[2]
b[0]=2
b[1]=b[b[0]]
b[0]=b[1]
.
g[2]
G[10]
g[0]=0
g[1]=G[0]
.
a[2147483647]
a[0]=1
B[2]
B[a[0]]=2
a[B[a[0]]]=3
a[2147483646]=a[2]
.
.


Output

2
2
2
3
4
0

Solution (in CPP):

Solution:
#include <bits/stdc++.h>

typedef long long LL;
typedef std::pair<int,int> PII;

typedef struct ParserState {
    int pos, len;
    std::string str;
    std::deque<int> stack;

    bool isEOF() {return pos >= len;}
    bool isNotEOF() {return pos < len;}

    char getCh() {
        return pos < len ? str[pos++] : -1;
    }
    char seek() {
        return pos < len ? str[pos] : -1;
    }
    char seek(int offset) {
        return (pos+offset) < len ? str[pos+offset] : -1;
    }
    std::string lookAhead(int l) {
        return str.substr(pos, l);
    }

    void setBackrack(){stack.push_front(pos);}
    bool backtrack(){
        if(stack.empty()) return false;
        pos = stack.front();
        stack.pop_front();
        return true;
    }

    bool isDigit(){return isDigit(0);}
    bool isDigit(int offset) {
        char c = seek(offset);
        return c != -1 && c >= '0' && c <= '9';
    }
    bool isUpperAlpha(){return isUpperAlpha(0);}
    bool isUpperAlpha(int offset) {
        char c = seek(offset);
        return c != -1 && c >= 'A' && c <= 'Z';
    }
    bool isLowerAlpha(){return isLowerAlpha(0);}
    bool isLowerAlpha(int offset) {
        char c = seek(offset);
        return c != -1 && c >= 'a' && c <= 'z';
    }
}State;

/*
    <program> := { <line> \n}*

    <line> := <declaration> | <assignment>
    <declaration> := <arrayname> '[' <number> ']'
    <assignment>  := <arrayname> '[' <expression> ']' '=' <expression>
    <expression>  := <number> | <arrayname> '[' <expression> ']'
    <number> := [0-9]+

    <array> := <alpha> '[' <number> ']'
*/

std::map<char, int > size;
std::map<char, std::map<int,int> > initialized;

int  parseNumber(State*);
PII  parseArray(State*);
PII  parseExpr(State*);
bool parseLine(State*);

bool isRange(int name, int index) {
    return size.count((char)name) > 0 && index < size[(char)name];
}
bool isSet(int name, int index) {
    return isRange((char)name, index) && initialized[(char)name].count(index) > 0;
}

void decl(int name, int len) {
    size[(char)name] = len;
}
bool set(int name, int index, int value) {
    if(!isRange((char)name, index)) return false;
    initialized[(char)name][index] = value;
    return true;
}
int get(int name, int index) {
    if(!isSet((char)name, index)) return -1;
    return initialized[(char)name][index];
}

int parseNumber(State *state) {
    int res = 0;
    while(state->isNotEOF() && state->isDigit()) {
        res *= 10;
        res += (int)(state->getCh() - '0');
    }
    return res;
}

PII parseArray(State *state) {
    int name = (int)state->getCh();
    state->getCh(); // eat [
    int num = parseNumber(state);
    state->getCh(); // eat ]
    return std::make_pair(name, num);
}

PII parseExpr(State *state) {
    if(state->isDigit()) return std::make_pair(parseNumber(state), -1);

    int name = (int)state->getCh();
    state->getCh(); // eat [
    PII sub = parseExpr(state);
    state->getCh(); // eat ]

    if(sub.first < 0) return std::make_pair(-1, 0);
    if(sub.second < 0) {
        //integer literal access
        return std::make_pair(name, sub.first);
    }
    if(!isSet(sub.first, sub.second)) return std::make_pair(-1, 0);

    return std::make_pair(name, get(sub.first, sub.second));
}

bool parseLine(State *state) {
    PII ary = parseExpr(state);
    if(ary.first < 0) return false;

    if(state->isNotEOF() && state->seek() == '=') {
        if(isRange(ary.first, ary.second) == false) return false;

        state->getCh();// eat =
        PII expr = parseExpr(state);
        if(expr.first < 0) return false;

        int val = expr.first;
        if(expr.second >= 0) {
            if(!isSet(expr.first, expr.second)) return false;
            val = get(expr.first, expr.second);
        }
        set(ary.first, ary.second, val);
    } else {
        decl(ary.first, ary.second);
    }
    return true;
}



int main() {
    std::string S;
    while(std::cin >> S && S[0] != '.') {
        int line = 0, res = -1;
        size.clear();
        initialized.clear();
        do {
            line++;
            State state = State{0, (int)S.length(), S};
            if(res == -1 && parseLine(&state) == false) {
                res = line;
            }
        }while(std::cin >> S && S[0] != '.');
        std::cout << std::max(res, 0) << std::endl;
    }
}