Time Limit: 1000 ms
Memory Limit: 65535 ms
A simple 8-digit electronic calculator contains the following buttons: “1234567890+-*/=” (no quotes). It can be divided into the following categories:
You can input any number with digital buttons (ignore leading zero). Notice, the LED of calculator can only display 8 digits. So when the number of digits large than eight, only the first eight digits will be retained. And when the number of one result’s digits large than eight, error occurs.
For simplicity, all operations are integer operations. Some continuous operators, the last one is valid. When an operator button is pressed, the calculation before that will be completed.
If the second operand is missing, you can think it equal the first operand. More than one continuous equal-sign means repeat the operation. You can observe the following examples.