最長公共子序列

#include<iostream>
#include<cstring>
#include<string.h>
#include<cstdio>
using namespace std;

void LCSLength(int m, int n, char *x, char *y);
void LCS(int i, int j, char *x);
int ans = 0;
int c[100][100],b[100][100];
int main(){
    int m,n,num;
    char x[100],y[100];
    cin >> num;
    while(num--){
        ans = 0;
        cin >> x;
        cin >> y;
        m = strlen(x);
        n = strlen(y);
        LCSLength(m,n,x,y);
        LCS(m,n,x);
        cout << "\n" <<ans <<endl;
    }
    return 0;
}
void LCSLength(int m, int n, char *x, char *y){
    for(int i = 0; i <= m; i++){
        c[i][0] = 0;
    }
    for(int i = 0; i <= n; i++){
        c[0][i] = 0;
    }
    for(int i = 1; i <= m; i++){
        for(int j = 1; j <= n; j++){
            if(x[i-1] == y[j-1]){
                c[i][j] = c[i][j] + 1;
                b[i][j] = 1;
            }else if(c[i-1][j] >= c[i][j-1]){
                c[i][j] = c[i-1][j];
                b[i][j] = 2;
            }else{
                c[i][j] = c[i][j-1];
                b[i][j] = 3;
            }
        }
    }
}
void LCS(int i, int j, char *x){
    if(i==0&&j==0){
        return;
    }
    if(b[i][j] == 1){
        LCS(i-1,j-1,x);
        ans++;
        cout << x[i-1];
    }else if(b[i][j] == 2){
        LCS(i-1,j,x);
    }else{
        LCS(i,j-1,x);
    }
}

第一個樣例過了，後面的有bug ,以後有時間再debug