#include<cstdio>

#include<cstring>

#include<queue>

#include<string>

#include<algorithm>

#include<map>

#include<iostream>

using namespace std;

const int maxn=+;

int T,n;

int dp[maxn][*maxn];

int a[maxn],b[maxn];

void init()

{

    for(int i=;i<=n;i++)

        for(int j=;j<=;j++)

            dp[i][j]=0x7fffffff;

}

void read()

{

    scanf("%d",&n);

    for(int i=;i<=n;i++) scanf("%d%d",&a[i],&b[i]);

}

void work()

{

    dp[][a[]+]=dp[][-b[]+]=;

    for(int i=;i<=n;i++)

    {

        for(int j=;j<=;j++)

        {

            if(dp[i-][j]==0x7fffffff) continue;

            int tmp=j-;

            if(tmp>=)

            {

                dp[i][a[i]+]=min(dp[i][a[i]+],dp[i-][j]+tmp);

                if(b[i]>=tmp) dp[i][tmp-b[i]+]=min(dp[i][tmp-b[i]+],dp[i-][j]+tmp);

                else if(b[i]<tmp) dp[i][tmp-b[i]+]=min(dp[i][tmp-b[i]+],dp[i-][j]+b[i]);

            }

            else if(tmp<)

            {

                tmp=-tmp;

                if(dp[i-][j]+tmp<dp[i][-b[i]+]) dp[i][-b[i]+]=min(dp[i][-b[i]+],dp[i-][j]+tmp);

                if(a[i]<=tmp) dp[i][a[i]-tmp+]=min(dp[i][a[i]-tmp+],dp[i-][j]+a[i]);

                else if(a[i]>tmp) dp[i][a[i]-tmp+]=min(dp[i][a[i]-tmp+],dp[i-][j]+tmp);

            }

        }

    }

    int ans=0x7fffffff;

    for(int j=;j<=;j++)

    {

        if(dp[n][j]==0x7fffffff) continue;

        ans=min(ans,dp[n][j]+abs(j-));

    }

    printf("%d\n",ans);

}

int main()

{

    scanf("%d",&T);

    while(T--)

    {

        read();

        init();

        work();

    }

    return ;

}