find and remove element from array (solidity)

Question

I've tackled a task: find a specific address in a sheet, move it to the end of the sheet, and remove it via a function pop: here is the code:

function removeAccount(address _account) external{
        uint counter = arrayOfAccounts.length;
        uint index;
        for(uint i; i < counter; i++) {
            if(arrayOfAccounts[i] == _account){
                index = i;
                break;
            }
        for(uint i = index; i < counter-1; i++){
                arrayOfAccounts[i] = arrayOfAccounts[i + 1];
            }
            arrayOfAccounts.pop();
        }
    }
        }
    }

transact to Wote.removeAccount errored: VM error: revert.

revert The transaction has been reverted to the initial state. Note: The called function should be payable if you send value and the value you send should be less than your current balance. Debug the transaction to get more information.

Answer 1

In case you dont care about addresses order

function removeAccount(address _account) external {
    if(arrayOfAccounts.length == 1) {
        arrayOfAccounts.pop();
    }
    else if(arrayOfAccounts[arrayOfAccounts.length - 1] == _account) {
        arrayOfAccounts.pop();
    }
    else {
        for (uint i = 0; i < arrayOfAccounts.length - 1; i++) {
            if(_account == arrayOfAccounts[i]) {
                arrayOfAccounts[i] = arrayOfAccounts[arrayOfAccounts.length - 1];
                arrayOfAccounts.pop();
            }
        }
        
    }
}

Answer 2

If order matters

function removeAccount(address _account) external{
        uint counter = arrayOfAccounts.length;
        for(uint i; i < counter; i++) {
            if(arrayOfAccounts[i] == _account){
                for(uint j = i; j < counter-1; j++){
                    arrayOfAccounts[j] = arrayOfAccounts[j + 1];
                }
                arrayOfAccounts.pop();
                break;
            }
        }
    }
}

Else if order doesn't matter

function removeAccount(address _account) external{
    uint numAccounts = arrayOfAccounts.length;
    for(uint i = 0; i < numAccounts; i++) {
        if(arrayOfAccounts[i] == _account){    // if _account is in the array
            arrayOfAccounts[i] = arrayOfAccounts[numAccounts - 1];    // move the last account to _account's index
            arrayOfAccounts.pop();    // remove the last account
            break;
        }
    }
}

Answer 3

The reason is just simple. You used the second for loop inside the first for loop. And also please initialize the index with counter ;

uint256 index = counter;

And pop only when index is less than counter