有个介绍，以前些的，这里贴个乱乱的代码，有错误请指正
有分量了后，缩点就好弄了，硬搞就可以
矩阵存储 ：
#include <stdio.h>
#include <string.h>
int map[100][100], mapt[100][100], n, m, ans, f[100], s[100], time;
bool judge[100];
void dfs(int v){//正图dfs
int i;judge[v] = true;
for(i = 1; i <= n; i++){
if(map[v][i] && !judge[i]){
dfs(i);
}
}
f[v] = ++time;
}
void dfst(int v){//反图dfs
int i; judge[v] = true;
for(i = 1; i <= n; i++){
if(mapt[v][i] && !judge[i]){
dfst(i);
}
}
}
int main(){
freopen("strong.in", "r", stdin);
freopen("strong.out", "w", stdout);
int i, j, u, v;
while(scanf("%d%d", &n, &m) != -1){
memset(map, 0, sizeof(map));
memset(mapt, 0, sizeof(mapt));
memset(f, 0, sizeof(f));
time = ans = 0;
for(i = 0; i < m; i++){
scanf("%d%d", &u, &v);
map[u][v] = true;
mapt[v][u] = true;
}
for(i = 1; i <= n; i++)if(!judge[i])dfs(i);
memset(judge, 0, sizeof(judge));
for(i = 1; i <= n; i++)s[f[i]] = i;//按照拓扑序列dfs倒置矩阵
for(i = n; i >= 1; i--){
if(!judge[s[i]]){
dfst(s[i]);
ans++;//倒置矩阵的连同分量个数就是结果了。
}
}
printf("storng num = %d\n", ans);
}
return 0;
}
链表存储 ：
#include <stdio.h>
#include <string.h>
struct e{
int v;
e* next;
};
e* map[100], *mapt[100], edge[1000], edget[1000];
int m, n, el, etl, ans, f[100], s[100], time;
bool judge[100];
void dfs(int v){
int i, t;e* l = map[v];
judge[v] = true;
while(l){
t = l->v;
if(!judge[t])dfs(t);
l = l->next;
}f[v] = ++time;
}
void dfst(int v){
int i, t; e* l = mapt[v];
judge[v] = true;
while(l){
t = l->v;
if(!judge[t])dfst(t);
l = l->next;
}
}
int main(){
freopen("strong_link.in", "r", stdin);
freopen("strong_link.out", "w", stdout);
int i, j, u, v;
while(scanf("%d%d", &n, &m) != -1){
memset(map, 0, sizeof(map));
memset(mapt, 0, sizeof(mapt));
memset(f, 0, sizeof(f));
memset(s, 0, sizeof(s));
el = ans = etl = time = 0;
for(i = 0; i < m; i++){
scanf("%d%d", &u, &v);
edge[el].v = v;
edge[el].next = map[u];
map[u] = &edge[el++];
edget[etl].v = u;
edget[etl].next = mapt[v];
mapt[v] = &edget[etl++];
}
for(i = 1; i <= n; i++)if(!judge[i])dfs(i);
for(i = 1; i <= n; i++)s[f[i]] = i;
memset(judge, 0, sizeof(judge));
for(i = n; i >= 1; i--){
if(!judge[s[i]]){
dfst(s[i]);
ans++;
}
}
printf("strong num = %d\n", ans);
}
return 0;
}