assigning value to arguments while recursion
I have a small doubt in this recursion
when will called in main for first time the value of p will be -1
say when first recursive call will be made to dfs(2,3)(let u=2,v=3)
then will 3 be converted to -1 automatically ? or (2,3) will be passed
as it is and -1 will be for only first recursive call
void dfs(int v, int p = -1) {
par[v] = p;
for (int u : G[v]) {
if (u == p) continue;
f[u] += f[v];
printf("%d",f[u]);
dfs(u, v);
}
}
c++ recursion
add a comment |
I have a small doubt in this recursion
when will called in main for first time the value of p will be -1
say when first recursive call will be made to dfs(2,3)(let u=2,v=3)
then will 3 be converted to -1 automatically ? or (2,3) will be passed
as it is and -1 will be for only first recursive call
void dfs(int v, int p = -1) {
par[v] = p;
for (int u : G[v]) {
if (u == p) continue;
f[u] += f[v];
printf("%d",f[u]);
dfs(u, v);
}
}
c++ recursion
1
If you calldfswith two arguments, both will be set tovandprespectively. No default value if you pass two arguments.
– Matthieu Brucher
Nov 23 '18 at 17:15
add a comment |
I have a small doubt in this recursion
when will called in main for first time the value of p will be -1
say when first recursive call will be made to dfs(2,3)(let u=2,v=3)
then will 3 be converted to -1 automatically ? or (2,3) will be passed
as it is and -1 will be for only first recursive call
void dfs(int v, int p = -1) {
par[v] = p;
for (int u : G[v]) {
if (u == p) continue;
f[u] += f[v];
printf("%d",f[u]);
dfs(u, v);
}
}
c++ recursion
I have a small doubt in this recursion
when will called in main for first time the value of p will be -1
say when first recursive call will be made to dfs(2,3)(let u=2,v=3)
then will 3 be converted to -1 automatically ? or (2,3) will be passed
as it is and -1 will be for only first recursive call
void dfs(int v, int p = -1) {
par[v] = p;
for (int u : G[v]) {
if (u == p) continue;
f[u] += f[v];
printf("%d",f[u]);
dfs(u, v);
}
}
c++ recursion
c++ recursion
edited Nov 23 '18 at 17:08
πάντα ῥεῖ
73.1k976141
73.1k976141
asked Nov 23 '18 at 17:07
user10628441
1
If you calldfswith two arguments, both will be set tovandprespectively. No default value if you pass two arguments.
– Matthieu Brucher
Nov 23 '18 at 17:15
add a comment |
1
If you calldfswith two arguments, both will be set tovandprespectively. No default value if you pass two arguments.
– Matthieu Brucher
Nov 23 '18 at 17:15
1
1
If you call
dfs with two arguments, both will be set to v and p respectively. No default value if you pass two arguments.– Matthieu Brucher
Nov 23 '18 at 17:15
If you call
dfs with two arguments, both will be set to v and p respectively. No default value if you pass two arguments.– Matthieu Brucher
Nov 23 '18 at 17:15
add a comment |
1 Answer
1
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oldest
votes
In void dfs(int v, int p = -1), -1 is the default value.
so when you write
dfs(42);
it is in fact
dfs(42, -1);
but if you provide argument, default value is not used.
add a comment |
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In void dfs(int v, int p = -1), -1 is the default value.
so when you write
dfs(42);
it is in fact
dfs(42, -1);
but if you provide argument, default value is not used.
add a comment |
In void dfs(int v, int p = -1), -1 is the default value.
so when you write
dfs(42);
it is in fact
dfs(42, -1);
but if you provide argument, default value is not used.
add a comment |
In void dfs(int v, int p = -1), -1 is the default value.
so when you write
dfs(42);
it is in fact
dfs(42, -1);
but if you provide argument, default value is not used.
In void dfs(int v, int p = -1), -1 is the default value.
so when you write
dfs(42);
it is in fact
dfs(42, -1);
but if you provide argument, default value is not used.
answered Nov 23 '18 at 17:16
Jarod42Jarod42
117k12103185
117k12103185
add a comment |
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1
If you call
dfswith two arguments, both will be set tovandprespectively. No default value if you pass two arguments.– Matthieu Brucher
Nov 23 '18 at 17:15