KMP算法加NEXT数组

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//顺序表KMP算法 
int pMatch(PSeqString t,pSeqString p,int *next){
    int i,j;
    i = 0;
    j = 0;
    while(i < p->n && j < t->n){
        if(i == -1 || p->c[i] == t->c[i]){
            i++;
            j++;
        }else{
            i = next[i];
        }
    }
    if(i >= p->n){
        return (j-p->n+1);
    }else{
        return -1;
    }
}
//求next数组((未优化之前))
makeNext(PSeqString p,int *next){
    int i = 0;
    int k = -1;
    next[0] = -1;
    while(i < p->n-1){
        while(k >= 0 && p->c[i] != p->c[k]){
            k = next[k];
        }
        i++;
        k++;
        next[i] = k;
    }
} 
//求next数组（优化后）
makeNext(PSeqString p,int *next){
    int i = 0;
    int k = -1;
    next[0] = -1;
    while(i < p->n-1){
        while(k >= 0 && p->c[i] != p->c[k]){
            k = next[k];
        }
        i++;
        k++;
    }
    if(p->c[i] == p->c[k]){
        next[i] = next[k];
    }else{
        next[i] = k;
    }
}