#include <iostream>#include <string>#define MAX_N 75using namespace std;char graph[MAX_N + 1][MAX_N + 1];string num[MAX_N + 1][MAX_N + 1];int W, H;string maxNum;bool strcmp(const string &s1, const string &s2){ int len1 = s1.length(), len2 = s2.length(); if(len1 < len2) return false; else if(len1 > len2) return true; else return s1 >= s2;}void trim(string &val){ while(val.length() > 0 && val[0] == '0') val = val.substr(1, val.length() - 1);}int main(){ int i, j; while(scanf("%d%d", &W, &H) && (W + H) != 0) { maxNum = "0"; for(i = 1; i <= H; i++) { scanf("%s", &graph[i][1]); for(j = 1; j <= W; j++) { if(graph[i][j] >= '0' && graph[i][j] <= '9') { num[i][j] = graph[i][j]; trim(num[i][j]); if(j >= 2 && (i == 1 || strcmp(num[i][j - 1], num[i - 1][j]))) num[i][j] = num[i][j - 1] + graph[i][j]; if(i >= 2 && (j == 1 || strcmp(num[i - 1][j], num[i][j - 1]))) num[i][j] = num[i - 1][j] + graph[i][j]; } else num[i][j] = "0"; trim(num[i][j]); if(strcmp(num[i][j], maxNum)) maxNum = num[i][j]; } } cout<<maxNum<<endl; } return 0;}
