well this coming week im spending nothing cos i spent it the pub this afternoon. 
make all my meals up at home and freeze em and eat em through the week as they defrost maybe have to buy an extra bottle of milk through the week for my weetabix and brew 
o and on a friday il treat myself to whatever i can find 
When I am in France. I get a morning espresso double and ask for a ham baguette to take out. That does me until night time with maybe another coffee on the motorway or in a factory.
Then I always eat a proper French meal with wine which normally costs between €15 to €18 with a couple of kir’s. Continental night out money is £30 or thereabouts so it is easily paid for with a bit left over for duty free on the way home. On the train I will have a French breakfast or just coffee as it is too expensive for rubbish food.
In the UK I will probably have a cafe or pub meal at night and I always have teabags and a flask of hot water. That will probably cost a tenner, again from my night out money.