hdu 1711 Number Sequence (KMP - 初步)

#include <iostream>
#include <cstring>
#include <string>
#include <cstdio>

using namespace std;
const int N = 1000005;
const int M = 10005;

int s
;
int t[M];
int next[M];
void get_next(int len) {
int i, j;
i = 0, j = -1;
next[0] = -1;
while(i < len-1) {
if(j == -1 || t[i] == t[j]) {
i++, j++; next[i] = j;
}
else {
j = next[j];
}
}
}
int kmp(int sl, int tl) {
int i = 0, j = 0;
while(i < sl && j < tl) {
if(j == -1 || s[i] == t[j]) {
i++, j++;
}
else {
j = next[j];
}
}
if(j == tl) {
return i - j + 1;
}
else return -1;
}
int main() {
int T, n, m, ans;
cin >> T;
while(T--) {
scanf("%d%d", &n, &m);
int i;
for(i = 0; i < n; i++) {
scanf("%d", s+i);
}
for(i = 0; i < m; i++) {
scanf("%d", t+i);
}
get_next(m);
ans = kmp(n, m);
printf("%d\n", ans);
}
return 0;
}