init commit

3sem/cnts/contest2/01.c

@@ -0,0 +1,27 @@
+// #include <stdio.h>
+
+typedef int STYPE;
+typedef unsigned int UTYPE;
+
+STYPE
+bit_reverse(STYPE value)
+{
+    UTYPE result = 0;
+    UTYPE uvalue = (UTYPE) value;
+    for (int i = 0; i < sizeof(STYPE) * 8; i++) {
+        result <<= 1;
+        result |= uvalue & 1;
+        uvalue >>= 1;
+    }
+    return (STYPE) result;
+}
+
+// int main(void) {
+
+//     STYPE value = 0b10101010;
+//     STYPE result = bit_reverse(value);
+//     printf("%d\n", result);
+//     printf("%ld\n", sizeof(STYPE));
+
+//     return 0;
+// }

3sem/cnts/contest2/02.c

@@ -0,0 +1,41 @@
+#include <stdio.h>
+#include <stdint.h>
+#include <errno.h>
+#include <stdlib.h>
+
+int
+main(int argc, char *argv[])
+{
+    long long res_pos = 0, res_neg = 0;
+
+    for (int i = 1; i < argc; i++) {
+        char *p;
+        errno = 0;
+        long long val = strtol(argv[i], &p, 10);
+        if (*p || errno || (int32_t) val != val || argv[i] == p) {
+            return 1;
+        }
+        // int32_t tmp;
+        if (val >= 0) {
+            // if (!__builtin_add_overflow(res_pos, val, &tmp)) {
+            res_pos += val;
+            // }
+        } else {
+            // if (!__builtin_add_overflow(res_neg, val, &tmp)) {
+            res_neg += val;
+            // }
+        }
+    }
+
+    // if (!(res_neg && res_pos)) {
+    //     printf("0\n");
+    // } else {
+    //     printf("%d\n", res_pos);
+    //     printf("%d\n", res_neg);
+    // }
+
+    printf("%lld\n", res_pos);
+    printf("%lld\n", res_neg);
+
+    return 0;
+}

3sem/cnts/contest2/03.c

@@ -0,0 +1,39 @@
+#include <stdio.h>
+#include <stdint.h>
+#include <errno.h>
+#include <stdlib.h>
+#include <math.h>
+
+enum
+{
+    PRCN = 10000,
+};
+
+int
+main(int argc, char *argv[])
+{
+    long double a = 0;
+
+    for (int i = 1; i < argc; i++) {
+        char *p;
+        errno = 0;
+        long double val = strtod(argv[i], &p);
+        if (*p || errno || argv[i] == p) {
+            return 1;
+        }
+
+        if (i == 1) {
+            a = val * PRCN;
+        } else {
+            a = round(a * (100.L + val) / 100.L);
+        }
+    }
+
+    if (argc == 1) {
+        return 1;
+    }
+
+    printf("%.4Lf\n", a / PRCN);
+
+    return 0;
+}

3sem/cnts/contest2/04.c

@@ -0,0 +1,22 @@
+#include <stdio.h>
+
+enum
+{
+    MY_INT_MAX = ~0u >> (!0),
+    MY_INT_MIN = ~(~0u >> (!0))
+};
+
+int
+satsum(int v1, int v2)
+{
+    int sum;
+    if (!__builtin_add_overflow(v1, v2, &sum)) {
+        return sum;
+    } else if (v1 > 0) {
+        return MY_INT_MAX;
+    } else {
+        return MY_INT_MIN;
+    }
+
+    return 0;
+}