'commit'

TangDou/LuoGuBook/第8章模拟与高精度/P1303_2.cpp

@@ -0,0 +1,44 @@
+#include <bits/stdc++.h>
+
+using namespace std;
+
+/**
+ * 功能：高精度乘高精度模板
+ * @param A
+ * @param b
+ * @return
+ */
+vector<int> mul(vector<int> &A, vector<int> &B) {
+    //初始化大小
+    vector<int> C(A.size() + B.size());
+    //先放里再说
+    for (int i = 0; i < A.size(); i++)
+        for (int j = 0; j < B.size(); j++)
+            C[i + j] += A[i] * B[j];
+
+    //处理余数
+    for (int i = 0, t = 0; i < C.size(); i++) {
+        t += C[i];
+        if (i >= C.size()) C.push_back(t % 10);
+        else C[i] = t % 10;
+        t /= 10;
+    }
+    //去掉前导0
+    while (C.size() > 1 && C.back() == 0) C.pop_back();
+    return C;
+}
+
+int main() {
+    string a, b;
+    cin >> a >> b;
+    //准备动作
+    vector<int> A, B;
+    for (int i = a.size() - 1; i >= 0; i--) A.push_back(a[i] - '0');
+    for (int i = b.size() - 1; i >= 0; i--) B.push_back(b[i] - '0');
+    //计算
+    vector<int> C = mul(A, B);
+    //倒序输出
+    for (int i = C.size() - 1; i >= 0; i--) cout << C[i];
+    return 0;
+}
+