
#include <stdio.h>
#include <math.h>
#include <string.h>

int main(){
    
    int ap,bp,cp,t;
    char a[999],b[999],c[82];
    
    scanf("%d",&t);
    while (scanf("%s %s",a,b)) {
        ap = strlen(a);
        bp = strlen(b);
        c[cp=(ap>80 || bp>80)? 0:81]='\0';
        t=0;
        while ((t||ap||bp) && cp>0) {
            t +=(ap? a[--ap]-'0':0) + (bp? b[--bp]-'0':0);
            c[--cp] = t%10 + '0';
            t /=10;
        }
        if(cp>0) printf(&c[cp]);
        else printf("overflow");
        printf("\n");
    }
    
    return 0;
    
}