Defined in header `<stdlib.h>` | ||
---|---|---|

div_t div( int x, int y ); | (1) | |

ldiv_t ldiv( long x, long y ); | (2) | |

lldiv_t lldiv( long long x, long long y ); | (3) | (since C99) |

Defined in header `<inttypes.h>` | ||

imaxdiv_t imaxdiv( intmax_t x, intmax_t y ); | (4) | (since C99) |

Computes both the quotient and the remainder of the division of the numerator `x`

by the denominator `y`

.

Computes quotient and remainder simultaneously. The quotient is the algebraic quotient with any fractional part discarded (truncated towards zero). The remainder is such that | (until C99) |

Computes the quotient (the result of the expression | (since C99) |

x, y | - | integer values |

If both the remainder and the quotient can be represented as objects of the corresponding type (int, long, long long, imaxdiv_t, respectively), returns both as an object of type `div_t`

, `ldiv_t`

, `lldiv_t`

, `imaxdiv_t`

defined as follows:

struct div_t { int quot; int rem; };

or.

struct div_t { int rem; int quot; };

struct ldiv_t { long quot; long rem; };

or.

struct ldiv_t { long rem; long quot; };

struct lldiv_t { long long quot; long long rem; };

or.

struct lldiv_t { long long rem; long long quot; };

struct imaxdiv_t { intmax_t quot; intmax_t rem; };

or.

struct imaxdiv_t { intmax_t rem; intmax_t quot; };

If either the remainder or the quotient cannot be represented, the behavior is undefined.

Until C99, the rounding direction of the quotient and the sign of the remainder in the built-in division and remainder operators was implementation-defined if either of the operands was negative, but it was well-defined in `div`

and `ldiv`

.

On many platforms, a single CPU instruction obtains both the quotient and the remainder, and this function may leverage that, although compilers are generally able to merge nearby / and % where suitable.

#include <stdio.h> #include <math.h> #include <stdlib.h> // demo only: does not check for buffer overflow void itoa(int n, int base, char* buf) { div_t dv = {.quot = n}; char* p = buf; do { dv = div(dv.quot, base); *p++ = "0123456789abcdef"[abs(dv.rem)]; } while(dv.quot); if(n<0) *p++ = '-'; *p-- = '\0'; while(buf < p) { char c = *p; *p-- = *buf; *buf++ = c; } // reverse } int main(void) { char buf[100]; itoa(12346, 10, buf); printf("%s\n", buf); itoa(-12346, 10, buf); printf("%s\n", buf); itoa(65535, 16, buf); printf("%s\n", buf); }

Output:

12346 -12346 ffff

- C11 standard (ISO/IEC 9899:2011):
- 7.8.2.2 The imaxdiv function (p: 219)
- 7.22.6.2 The div, ldiv and lldiv functions (p: 356)
- C99 standard (ISO/IEC 9899:1999):
- 7.8.2.2 The imaxdiv function (p: 200)
- 7.20.6.2 The div, ldiv and lldiv functions (p: 320)
- C89/C90 standard (ISO/IEC 9899:1990):
- 4.10 div_t, ldiv_t
- 4.10.6.2 The div function
- 4.10.6.4 The ldiv function

(C99)(C99) | computes remainder of the floating-point division operation (function) |

(C99)(C99)(C99) | computes signed remainder of the floating-point division operation (function) |

(C99)(C99)(C99) | computes signed remainder as well as the three last bits of the division operation (function) |

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