fix: updated problem output since the numbers of combinations could be very high.

decode-ways/src/alternative_ac.cpp

@@ -3,6 +3,8 @@
 typedef long long ll;
 using namespace std;
 
+const int MOD = 1e9 + 7;
+
 ll numDecodings(string s)
 {
     if (s[0] == '0')
@@ -20,12 +22,14 @@ ll numDecodings(string s)
         if (current != '0')
         {
             next = dp2;
+            next %= MOD;
         }
 
         int code = stoi(aux);
         if (10 <= code && code <= 26)
         {
             next += dp1;
+            next %= MOD;
         }
         swap(dp1, dp2);
         swap(dp2, next);