char buf[1 << 23], *p1 = buf, *p2 = buf, obuf[1 << 23], *O = obuf;
#include <bits/stdc++.h>
using namespace std;
using namespace chrono;
int x;
int N = 20000000;
int read() {
int x = 0, f = 1; char ch = getchar();
for(; !isdigit(ch); ch = getchar()) f ^= (ch == '-');
for(; isdigit(ch); ch = getchar()) x = (x << 3) + (x << 1) + (ch xor 48);
return f ? x : -x;
}
void gen(int n){
srand(time(0));
FILE *fp = fopen("test.in", "w");
for(int i = 0; i < n; ++i){
int opt = rand() % 2;
if(opt) fprintf(fp, "%d ", rand());
else fprintf(fp, "%d ", -rand());
}
fclose(fp);
}
void test_read(int n){while(n--) x = read();}
void test_scanf(int n){while(n--) scanf("%d", &x);}
void test_cin(int n){while(n--) cin >> x;}
int main(){
#pragma region 预生成随机数
gen(N);
#pragma endregion
#pragma region 测试scanf
freopen("test.in", "r", stdin);
auto start = high_resolution_clock::now();
test_scanf(N);
auto end = high_resolution_clock::now();
printf("scanf: %d ms\n", duration_cast<milliseconds>(end - start).count());
fclose(stdin);
#pragma endregion
#pragma region 测试read
#undef getchar
freopen("test.in", "r", stdin);
start = high_resolution_clock::now();
test_read(N);
end = high_resolution_clock::now();
printf("read function: %d ms\n", duration_cast<milliseconds>(end - start).count());
fclose(stdin);
#pragma endregion
#pragma region 测试fread
#define getchar() (p1==p2&&(p2=(p1=buf)+fread(buf,1,1<<21,stdin),p1==p2)?EOF:*p1++)
freopen("test.in", "r", stdin);
start = high_resolution_clock::now();
test_read(N);
end = high_resolution_clock::now();
printf("fread function: %d ms\n", duration_cast<milliseconds>(end - start).count());
fclose(stdin);
#undef getchar
#pragma endregion
#pragma region 测试cin
freopen("test.in", "r", stdin);
start = high_resolution_clock::now();
test_cin(N);
end = high_resolution_clock::now();
printf("cin: %d ms\n", duration_cast<milliseconds>(end - start).count());
fclose(stdin);
#pragma endregion
#pragma region 测试untied cin
freopen("test.in", "r", stdin);
ios::sync_with_stdio(true);
cin.tie(nullptr);
start = high_resolution_clock::now();
test_cin(N);
end = high_resolution_clock::now();
printf("untied cin: %d ms\n", duration_cast<milliseconds>(end - start).count());
fclose(stdin);
#pragma endregion
#pragma region 测试unsync cin
freopen("test.in", "r", stdin);
ios::sync_with_stdio(false);
start = high_resolution_clock::now();
test_cin(N);
end = high_resolution_clock::now();
printf("unsync cin: %d ms\n", duration_cast<milliseconds>(end - start).count());
fclose(stdin);
#pragma endregion
#pragma region 测试fastest cin
freopen("test.in", "r", stdin);
ios::sync_with_stdio(false);
cin.tie(nullptr);
start = high_resolution_clock::now();
test_cin(N);
end = high_resolution_clock::now();
printf("fastest cin: %d ms\n", duration_cast<milliseconds>(end - start).count());
fclose(stdin);
#pragma endregion
return 0;
}
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