#include <stdio.h>
int main(void){
    int x,y,z;
    int ans=0;
    scanf("%d %d %d",&x,&y,&z);
    for(;;){
        if(x>0&&y>0){
            x--;
            y--;
            ans++;
        }
        else{break;}
    }
    ans=ans+(z/2);
    printf("%d\n",ans);
    return 0;
}