#include <stdio.h>

int main(){
    long long holiday1, holiday2, all;
    scanf("%lld%lld%lld",&holiday1,&holiday2,&all);

    if(all >= holiday1 && all >= holiday2){
    	printf("%lld",all - 2);
    }else if(all >= holiday1 || all >= holiday2){
    	printf("%lld",all - 1);
    }else if(all < holiday1 && all < holiday2){
    	printf("%lld",all);
    }
}